<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019b0f49-2a83-7856-be0f-86e439809b2c,g:544da959-9a88-4431-8575-1597c131eb5b-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/ConsolidatedStatementsofOperations" xlink:type="simple" xlink:href="hcat-20251231.xsd#ConsolidatedStatementsofOperations"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/ConsolidatedStatementsofOperations" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019b0f49-2d1b-7b9d-88be-2007a617c7b8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_StatementTable_019b0f49-2d1b-7b9d-88be-2007a617c7b8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019b0f49-2d1b-7144-a1d2-68f50e2d2b93" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019b0f49-2d1b-7b9d-88be-2007a617c7b8" xlink:to="loc_srt_ProductOrServiceAxis_019b0f49-2d1b-7144-a1d2-68f50e2d2b93" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b0f49-2d1b-7144-a1d2-68f50e2d2b93_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019b0f49-2d1b-7144-a1d2-68f50e2d2b93" xlink:to="loc_srt_ProductsAndServicesDomain_019b0f49-2d1b-7144-a1d2-68f50e2d2b93_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b0f49-2d1b-778c-87c1-d92a57296127" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019b0f49-2d1b-7144-a1d2-68f50e2d2b93" xlink:to="loc_srt_ProductsAndServicesDomain_019b0f49-2d1b-778c-87c1-d92a57296127" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyMember_019b0f49-2d1b-733a-9705-69a00a7739b1" xlink:href="hcat-20251231.xsd#hcat_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b0f49-2d1b-778c-87c1-d92a57296127" xlink:to="loc_hcat_TechnologyMember_019b0f49-2d1b-733a-9705-69a00a7739b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ProfessionalServicesMember_019b0f49-2d1b-75cb-bfb3-cd140eaa150a" xlink:href="hcat-20251231.xsd#hcat_ProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b0f49-2d1b-778c-87c1-d92a57296127" xlink:to="loc_hcat_ProfessionalServicesMember_019b0f49-2d1b-75cb-bfb3-cd140eaa150a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_019b0f49-2d1b-7c68-acef-18b463cc3b61" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_RevenuesAbstract_019b0f49-2d1b-7c68-acef-18b463cc3b61" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019b0f49-2d1b-7e30-b929-9d2daeb7e7cf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019b0f49-2d1b-7c68-acef-18b463cc3b61" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019b0f49-2d1b-7e30-b929-9d2daeb7e7cf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfRevenueAbstract_019b0f49-2d1b-7f6b-9b34-081e35d69ded" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_CostOfRevenueAbstract_019b0f49-2d1b-7f6b-9b34-081e35d69ded" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019b0f49-2d1b-78fb-8f74-d8f0831823a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfRevenueAbstract_019b0f49-2d1b-7f6b-9b34-081e35d69ded" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019b0f49-2d1b-78fb-8f74-d8f0831823a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpense_019b0f49-2d1b-77b2-b117-84708804d28d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:to="loc_us-gaap_SellingAndMarketingExpense_019b0f49-2d1b-77b2-b117-84708804d28d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_019b0f49-2d1b-7d59-bc41-6391ccafb653" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_019b0f49-2d1b-7d59-bc41-6391ccafb653" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019b0f49-2d1b-72bd-8e1e-5fcaca0e092f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019b0f49-2d1b-72bd-8e1e-5fcaca0e092f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_019b0f49-2d1b-70d3-b087-4a3cf6b55596" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:to="loc_us-gaap_DepreciationAndAmortization_019b0f49-2d1b-70d3-b087-4a3cf6b55596" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetImpairment_019c36a4-af17-784f-8f2a-85cb4a1cc0f5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillAndIntangibleAssetImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:to="loc_us-gaap_GoodwillAndIntangibleAssetImpairment_019c36a4-af17-784f-8f2a-85cb4a1cc0f5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_019b0f49-2d1b-7dc4-afd3-b52b4468a7c1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019b0f49-2d1b-7f6c-b0e6-3965289c2c58" xlink:to="loc_us-gaap_OperatingExpenses_019b0f49-2d1b-7dc4-afd3-b52b4468a7c1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019b0f49-2d1b-7d64-b9a2-133612c8db96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_OperatingIncomeLoss_019b0f49-2d1b-7d64-b9a2-133612c8db96" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_019b0f49-2d1b-77b6-9eb1-103eec3518f6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_019b0f49-2d1b-77b6-9eb1-103eec3518f6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossAttributableToParent_019b0f49-2d1b-7754-8048-15c0fcdca8bc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_IncomeLossAttributableToParent_019b0f49-2d1b-7754-8048-15c0fcdca8bc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019b0f49-2d1b-7aa4-a809-1b0104962b5b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019b0f49-2d1b-7aa4-a809-1b0104962b5b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019b0f49-2d1b-71a2-975d-bb3bcb36e1ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_NetIncomeLoss_019b0f49-2d1b-71a2-975d-bb3bcb36e1ee" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_019b0f49-2d1b-7b5b-b731-fdcf19a99580" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_EarningsPerShareBasic_019b0f49-2d1b-7b5b-b731-fdcf19a99580" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_019b0f49-2d1b-7d26-8b6a-88483ca7f163" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_EarningsPerShareDiluted_019b0f49-2d1b-7d26-8b6a-88483ca7f163" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019b0f49-2d1b-7546-8e4c-a13e3af53f03" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019b0f49-2d1b-7546-8e4c-a13e3af53f03" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019b0f49-2d1b-7a98-bfb2-c7227f7f11b4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7001-8361-5f7e085a74a8" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019b0f49-2d1b-7a98-bfb2-c7227f7f11b4" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/ConsolidatedStatementsofStockholdersEquity" xlink:type="simple" xlink:href="hcat-20251231.xsd#ConsolidatedStatementsofStockholdersEquity"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/ConsolidatedStatementsofStockholdersEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7384-950e-a18cabd70fec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019b0f49-2d1b-7179-8a3d-75590f37d224" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7384-950e-a18cabd70fec" xlink:to="loc_us-gaap_StatementTable_019b0f49-2d1b-7179-8a3d-75590f37d224" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019b0f49-2d1b-733b-85da-ec9f178443e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019b0f49-2d1b-7179-8a3d-75590f37d224" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019b0f49-2d1b-733b-85da-ec9f178443e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019b0f49-2d1b-733b-85da-ec9f178443e1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019b0f49-2d1b-733b-85da-ec9f178443e1" xlink:to="loc_us-gaap_EquityComponentDomain_019b0f49-2d1b-733b-85da-ec9f178443e1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019b0f49-2d1b-7afd-b312-940caf3ec751" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019b0f49-2d1b-733b-85da-ec9f178443e1" xlink:to="loc_us-gaap_EquityComponentDomain_019b0f49-2d1b-7afd-b312-940caf3ec751" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_019b0f49-2d1b-77e9-a227-f3a0872d94dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019b0f49-2d1b-7afd-b312-940caf3ec751" xlink:to="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_019b0f49-2d1b-77e9-a227-f3a0872d94dc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019b0f49-2d1b-7523-bd16-39bfe1144828" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019b0f49-2d1b-7afd-b312-940caf3ec751" xlink:to="loc_us-gaap_RetainedEarningsMember_019b0f49-2d1b-7523-bd16-39bfe1144828" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019b0f49-2d1b-7e20-a102-001823660197" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019b0f49-2d1b-7afd-b312-940caf3ec751" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019b0f49-2d1b-7e20-a102-001823660197" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019b0f49-2d1b-7384-950e-a18cabd70fec" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019b0f49-2d1b-7010-b472-0637170b0551" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019b0f49-2d1b-7010-b472-0637170b0551" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019b0f49-2d1b-7deb-abad-fac7fe7deead" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockholdersEquity_019b0f49-2d1b-7deb-abad-fac7fe7deead" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_019b0f49-2d1b-7a57-a171-efe9667ac2e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_019b0f49-2d1b-7a57-a171-efe9667ac2e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_019b0f49-2d1b-7027-95b8-5cc4dd6b4407" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_019b0f49-2d1b-7027-95b8-5cc4dd6b4407" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_019b0f49-2d1b-7932-b603-4e63eaf8aa3e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_019b0f49-2d1b-7932-b603-4e63eaf8aa3e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019b0f49-2d1b-7dfb-ae55-deb1e13a83b2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019b0f49-2d1b-7dfb-ae55-deb1e13a83b2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019b0f49-2d1b-7dcd-ba7f-6e5a064cd29a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019b0f49-2d1b-7dcd-ba7f-6e5a064cd29a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_019b0f49-2d1b-7769-bf6a-3c211280fba9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_019b0f49-2d1b-7769-bf6a-3c211280fba9" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019b0f49-2d1b-7f73-b02e-9771d746ba85" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019b0f49-2d1b-7f73-b02e-9771d746ba85" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_019b0f49-2d1b-742f-a83a-c4b988cdd2db" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_019b0f49-2d1b-742f-a83a-c4b988cdd2db" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_019b0f49-2d1b-7285-9128-808c816db441" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_019b0f49-2d1b-7285-9128-808c816db441" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_019b0f49-2d1b-7e8d-8979-32556a54e0ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_019b0f49-2d1b-7e8d-8979-32556a54e0ee" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_019b0f49-2d1b-7e1c-95fa-c436a6f8008a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_019b0f49-2d1b-7e1c-95fa-c436a6f8008a" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019b0f49-2d1b-7f9e-ac2a-cfa188e26a61" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_NetIncomeLoss_019b0f49-2d1b-7f9e-ac2a-cfa188e26a61" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019b0f49-2d1b-7d0e-8680-b5ed8fb8d1f9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019b0f49-2d1b-751b-904a-779a157e7116" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019b0f49-2d1b-7d0e-8680-b5ed8fb8d1f9" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019b0f49-2d1b-73bf-ae41-1265211dcc13" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019b0f49-2d1b-7f2b-98a3-4110c2a63490" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#DescriptionofBusinessandSummaryofSignificantAccountingPoliciesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsidiarySaleOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_019b0f49-2d1c-7b3e-8950-479b1346947c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_019b0f49-2d1c-7b3e-8950-479b1346947c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b0f49-2d1c-7162-acd0-743d1bf166d2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_019b0f49-2d1c-7b3e-8950-479b1346947c" xlink:to="loc_srt_RangeAxis_019b0f49-2d1c-7162-acd0-743d1bf166d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2d1c-7162-acd0-743d1bf166d2_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b0f49-2d1c-7162-acd0-743d1bf166d2" xlink:to="loc_srt_RangeMember_019b0f49-2d1c-7162-acd0-743d1bf166d2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2d1c-74c4-bae5-c7c95a92c0b2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b0f49-2d1c-7162-acd0-743d1bf166d2" xlink:to="loc_srt_RangeMember_019b0f49-2d1c-74c4-bae5-c7c95a92c0b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b0f49-2d1c-78d4-b1d9-9e23f3cdf74f" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2d1c-74c4-bae5-c7c95a92c0b2" xlink:to="loc_srt_MinimumMember_019b0f49-2d1c-78d4-b1d9-9e23f3cdf74f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b0f49-2d1c-7816-9370-4d391370a01e" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2d1c-74c4-bae5-c7c95a92c0b2" xlink:to="loc_srt_MaximumMember_019b0f49-2d1c-7816-9370-4d391370a01e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7dd0-8cac-d1df0ed61e16" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_019b0f49-2d1c-7b3e-8950-479b1346947c" xlink:to="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7dd0-8cac-d1df0ed61e16" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7dd0-8cac-d1df0ed61e16_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7dd0-8cac-d1df0ed61e16" xlink:to="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7dd0-8cac-d1df0ed61e16_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7ac5-a4fc-bb1444506c97" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7dd0-8cac-d1df0ed61e16" xlink:to="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7ac5-a4fc-bb1444506c97" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyAndProfessionalServicesMember_019b0f49-2d1c-7eb6-9de4-36a1c4deca8a" xlink:href="hcat-20251231.xsd#hcat_TechnologyAndProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7ac5-a4fc-bb1444506c97" xlink:to="loc_hcat_TechnologyAndProfessionalServicesMember_019b0f49-2d1c-7eb6-9de4-36a1c4deca8a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfOperatingSegments_019b0f49-2d1c-7de4-9d63-cad152e199c4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfOperatingSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_NumberOfOperatingSegments_019b0f49-2d1c-7de4-9d63-cad152e199c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_019b0f49-2d1c-72fb-aaa5-2727db86fd28" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_NumberOfReportableSegments_019b0f49-2d1c-72fb-aaa5-2727db86fd28" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractTerm_019b0f49-2d1c-7e08-a892-255220de7cee" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractTerm_019b0f49-2d1c-7e08-a892-255220de7cee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_RevenueFromSubscriptionContractTermofContract_019b0f49-2d1c-74c7-a02d-b38190282dc7" xlink:href="hcat-20251231.xsd#hcat_RevenueFromSubscriptionContractTermofContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_hcat_RevenueFromSubscriptionContractTermofContract_019b0f49-2d1c-74c7-a02d-b38190282dc7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod_019b0f49-2d1c-7f20-a3d2-087daae9c28f" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod_019b0f49-2d1c-7f20-a3d2-087daae9c28f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_RevenueFromSubscriptionsContractNoticeRequiredForTermination_019b0f49-2d1c-759a-9bbf-3b445d3bc244" xlink:href="hcat-20251231.xsd#hcat_RevenueFromSubscriptionsContractNoticeRequiredForTermination"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_hcat_RevenueFromSubscriptionsContractNoticeRequiredForTermination_019b0f49-2d1c-759a-9bbf-3b445d3bc244" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostNetCurrent_019b0f49-2d1c-7a33-a985-5374b4880c5a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_CapitalizedContractCostNetCurrent_019b0f49-2d1c-7a33-a985-5374b4880c5a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAmortizationPeriod_019b0f49-2d1c-79eb-a3aa-c5625e03c4f3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostAmortizationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_CapitalizedContractCostAmortizationPeriod_019b0f49-2d1c-79eb-a3aa-c5625e03c4f3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostNetNoncurrent_019b0f49-2d1c-7e45-a79a-e13a5eb106bb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostNetNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_CapitalizedContractCostNetNoncurrent_019b0f49-2d1c-7e45-a79a-e13a5eb106bb" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CommissionPaymentEstimatedBenefitPeriod_019b0f49-2d1c-7636-9f37-3be35e78b8f5" xlink:href="hcat-20251231.xsd#hcat_CommissionPaymentEstimatedBenefitPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_hcat_CommissionPaymentEstimatedBenefitPeriod_019b0f49-2d1c-7636-9f37-3be35e78b8f5" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense_019b0f49-2d1c-75aa-b43f-bfe7ea82a6bc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense_019b0f49-2d1c-75aa-b43f-bfe7ea82a6bc" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019b0f49-2d1c-76fa-b15a-b62053dbcc96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019b0f49-2d1c-76fa-b15a-b62053dbcc96" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_019b0f49-2d1c-7be2-967d-cae5f83228af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_019b0f49-2d1c-7be2-967d-cae5f83228af" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_019b0f49-2d1c-7ea8-a8d7-d2a38c263a1a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationAcquisitionRelatedCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_019b0f49-2d1c-7ea8-a8d7-d2a38c263a1a" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdvertisingExpense_019b0f49-2d1c-7e55-aaec-5c1896c7ee4d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdvertisingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_019b0f49-2d1c-7d28-9970-202f55453ecc" xlink:to="loc_us-gaap_AdvertisingExpense_019b0f49-2d1c-7e55-aaec-5c1896c7ee4d" xlink:type="arc" order="14"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesScheduleofPropertyandEquipmentUsefulLifeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#DescriptionofBusinessandSummaryofSignificantAccountingPoliciesScheduleofPropertyandEquipmentUsefulLifeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesScheduleofPropertyandEquipmentUsefulLifeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7a11-a85e-7377480d974c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7874-9841-469b867d05ef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7a11-a85e-7377480d974c" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7874-9841-469b867d05ef" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-71e6-8aa2-9fde41ceac9a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7874-9841-469b867d05ef" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-71e6-8aa2-9fde41ceac9a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-71e6-8aa2-9fde41ceac9a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-71e6-8aa2-9fde41ceac9a" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-71e6-8aa2-9fde41ceac9a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7724-a435-e739b6b20bd5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-71e6-8aa2-9fde41ceac9a" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7724-a435-e739b6b20bd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerEquipmentMember_019b0f49-2d1c-770c-864b-664fedf991fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComputerEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7724-a435-e739b6b20bd5" xlink:to="loc_us-gaap_ComputerEquipmentMember_019b0f49-2d1c-770c-864b-664fedf991fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_019b0f49-2d1c-7ee2-b938-26049bec4569" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7724-a435-e739b6b20bd5" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_019b0f49-2d1c-7ee2-b938-26049bec4569" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019b0f49-2d1c-7251-a899-8a186afd5a2a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7724-a435-e739b6b20bd5" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019b0f49-2d1c-7251-a899-8a186afd5a2a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareDevelopmentMember_019b0f49-2d1c-76bc-b0ed-08d1168ba72f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SoftwareDevelopmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7724-a435-e739b6b20bd5" xlink:to="loc_us-gaap_SoftwareDevelopmentMember_019b0f49-2d1c-76bc-b0ed-08d1168ba72f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b0f49-2d1c-7e79-807a-ce4646d2efbc" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7874-9841-469b867d05ef" xlink:to="loc_srt_RangeAxis_019b0f49-2d1c-7e79-807a-ce4646d2efbc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2d1c-7e79-807a-ce4646d2efbc_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b0f49-2d1c-7e79-807a-ce4646d2efbc" xlink:to="loc_srt_RangeMember_019b0f49-2d1c-7e79-807a-ce4646d2efbc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2d1c-77bb-bb2b-65cfa94c37d4" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b0f49-2d1c-7e79-807a-ce4646d2efbc" xlink:to="loc_srt_RangeMember_019b0f49-2d1c-77bb-bb2b-65cfa94c37d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b0f49-2d1c-7505-83db-d8c3291e89d7" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2d1c-77bb-bb2b-65cfa94c37d4" xlink:to="loc_srt_MinimumMember_019b0f49-2d1c-7505-83db-d8c3291e89d7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b0f49-2d1c-768d-a62b-7564a39301d8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2d1c-77bb-bb2b-65cfa94c37d4" xlink:to="loc_srt_MaximumMember_019b0f49-2d1c-768d-a62b-7564a39301d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_019b0f49-2d1c-7951-a666-dc0ced506567" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7a11-a85e-7377480d974c" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_019b0f49-2d1c-7951-a666-dc0ced506567" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesScheduleofIntangibleAssetsUsefulLifeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#DescriptionofBusinessandSummaryofSignificantAccountingPoliciesScheduleofIntangibleAssetsUsefulLifeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesScheduleofIntangibleAssetsUsefulLifeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b0f49-2d1c-78d7-afd3-cb0ff92d7343" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b0f49-2d1c-7254-b619-12ddd8e73b52" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b0f49-2d1c-78d7-afd3-cb0ff92d7343" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b0f49-2d1c-7254-b619-12ddd8e73b52" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b0f49-2d1c-7e76-b4ff-ea70cdadafe3" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b0f49-2d1c-7254-b619-12ddd8e73b52" xlink:to="loc_srt_RangeAxis_019b0f49-2d1c-7e76-b4ff-ea70cdadafe3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2d1c-7e76-b4ff-ea70cdadafe3_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b0f49-2d1c-7e76-b4ff-ea70cdadafe3" xlink:to="loc_srt_RangeMember_019b0f49-2d1c-7e76-b4ff-ea70cdadafe3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2d1c-7df4-a38a-cc97d5b326d9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b0f49-2d1c-7e76-b4ff-ea70cdadafe3" xlink:to="loc_srt_RangeMember_019b0f49-2d1c-7df4-a38a-cc97d5b326d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b0f49-2d1c-7a25-82a2-a9c0a2ef9b12" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2d1c-7df4-a38a-cc97d5b326d9" xlink:to="loc_srt_MinimumMember_019b0f49-2d1c-7a25-82a2-a9c0a2ef9b12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b0f49-2d1c-7514-8418-b3312201a9f3" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2d1c-7df4-a38a-cc97d5b326d9" xlink:to="loc_srt_MaximumMember_019b0f49-2d1c-7514-8418-b3312201a9f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7cd3-ab21-02f24db549ae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b0f49-2d1c-7254-b619-12ddd8e73b52" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7cd3-ab21-02f24db549ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7cd3-ab21-02f24db549ae_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7cd3-ab21-02f24db549ae" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7cd3-ab21-02f24db549ae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-72da-a7d0-f9ad96fd2073" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7cd3-ab21-02f24db549ae" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-72da-a7d0-f9ad96fd2073" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7bea-9632-7106f28586cf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-72da-a7d0-f9ad96fd2073" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7bea-9632-7106f28586cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ClientRelationshipsAndContractsMember_019b0f49-2d1c-7f29-8643-dde2fd037366" xlink:href="hcat-20251231.xsd#hcat_ClientRelationshipsAndContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-72da-a7d0-f9ad96fd2073" xlink:to="loc_hcat_ClientRelationshipsAndContractsMember_019b0f49-2d1c-7f29-8643-dde2fd037366" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_019b0f49-2d1c-7ae7-86f6-b1877f324d5a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComputerSoftwareIntangibleAssetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-72da-a7d0-f9ad96fd2073" xlink:to="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_019b0f49-2d1c-7ae7-86f6-b1877f324d5a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksMember_019b0f49-2d1c-75ff-b46a-1dc243e1a13b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TrademarksMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-72da-a7d0-f9ad96fd2073" xlink:to="loc_us-gaap_TrademarksMember_019b0f49-2d1c-75ff-b46a-1dc243e1a13b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_019b0f49-2d1c-7704-8198-ecd9c7d887e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b0f49-2d1c-78d7-afd3-cb0ff92d7343" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_019b0f49-2d1c-7704-8198-ecd9c7d887e6" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/BusinessCombinationsNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#BusinessCombinationsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/BusinessCombinationsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7e82-9b1a-24c6eba7eab8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7e82-9b1a-24c6eba7eab8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7889-8f8c-e96728c7bde9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7e82-9b1a-24c6eba7eab8" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7889-8f8c-e96728c7bde9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7889-8f8c-e96728c7bde9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7889-8f8c-e96728c7bde9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7889-8f8c-e96728c7bde9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7eeb-afb4-62b22686783a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7889-8f8c-e96728c7bde9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7eeb-afb4-62b22686783a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_IntrapriseHealthLLC.Member_019b0f49-2d1c-7821-a123-a7d2d9644450" xlink:href="hcat-20251231.xsd#hcat_IntrapriseHealthLLC.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7eeb-afb4-62b22686783a" xlink:to="loc_hcat_IntrapriseHealthLLC.Member_019b0f49-2d1c-7821-a123-a7d2d9644450" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_LumeonLtd.Member_019b0f49-2d1c-78c0-af89-df7fba661920" xlink:href="hcat-20251231.xsd#hcat_LumeonLtd.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7eeb-afb4-62b22686783a" xlink:to="loc_hcat_LumeonLtd.Member_019b0f49-2d1c-78c0-af89-df7fba661920" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CareviveSystemsInc.Member_019b0f49-2d1c-73ad-ba16-634c705b7c4e" xlink:href="hcat-20251231.xsd#hcat_CareviveSystemsInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7eeb-afb4-62b22686783a" xlink:to="loc_hcat_CareviveSystemsInc.Member_019b0f49-2d1c-73ad-ba16-634c705b7c4e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ERSCorporationMember_019b0f49-2d1c-7cc1-bb16-89f8221af294" xlink:href="hcat-20251231.xsd#hcat_ERSCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7eeb-afb4-62b22686783a" xlink:to="loc_hcat_ERSCorporationMember_019b0f49-2d1c-7cc1-bb16-89f8221af294" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_UpfrontHealthcareServicesMember_019c36c8-b3a4-79ca-880d-64f8339bd479" xlink:href="hcat-20251231.xsd#hcat_UpfrontHealthcareServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7eeb-afb4-62b22686783a" xlink:to="loc_hcat_UpfrontHealthcareServicesMember_019c36c8-b3a4-79ca-880d-64f8339bd479" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-78bb-8ed0-860db25c5089" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7e82-9b1a-24c6eba7eab8" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-78bb-8ed0-860db25c5089" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-78bb-8ed0-860db25c5089_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-78bb-8ed0-860db25c5089" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-78bb-8ed0-860db25c5089_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7122-8ba9-acb6f0b1a7f5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-78bb-8ed0-860db25c5089" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7122-8ba9-acb6f0b1a7f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ClientRelationshipsENTMember_019b0f49-2d1c-7c0d-87f1-b1c851826eaf" xlink:href="hcat-20251231.xsd#hcat_ClientRelationshipsENTMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7122-8ba9-acb6f0b1a7f5" xlink:to="loc_hcat_ClientRelationshipsENTMember_019b0f49-2d1c-7c0d-87f1-b1c851826eaf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ClientRelationshipsSMBMember_019b0f49-2d1c-7f8d-bea4-fdf56c6c8968" xlink:href="hcat-20251231.xsd#hcat_ClientRelationshipsSMBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7122-8ba9-acb6f0b1a7f5" xlink:to="loc_hcat_ClientRelationshipsSMBMember_019b0f49-2d1c-7f8d-bea4-fdf56c6c8968" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7536-87f0-630e98ba48ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7122-8ba9-acb6f0b1a7f5" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7536-87f0-630e98ba48ba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksMember_019b0f49-2d1c-72a8-861d-0075f5d7f0e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TrademarksMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7122-8ba9-acb6f0b1a7f5" xlink:to="loc_us-gaap_TrademarksMember_019b0f49-2d1c-72a8-861d-0075f5d7f0e1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_019b0f49-2d1c-7b14-b42c-fbb5386a6618" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7122-8ba9-acb6f0b1a7f5" xlink:to="loc_us-gaap_CustomerRelationshipsMember_019b0f49-2d1c-7b14-b42c-fbb5386a6618" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019b0f49-2d1c-77e1-8f38-f39040b2085f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7e82-9b1a-24c6eba7eab8" xlink:to="loc_us-gaap_AwardTypeAxis_019b0f49-2d1c-77e1-8f38-f39040b2085f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2d1c-77e1-8f38-f39040b2085f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2d1c-77e1-8f38-f39040b2085f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2d1c-77e1-8f38-f39040b2085f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2d1c-7a56-baaf-211064f1ad8c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2d1c-77e1-8f38-f39040b2085f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2d1c-7a56-baaf-211064f1ad8c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_019b0f49-2d1c-7269-b18b-e950af3cf88a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2d1c-7a56-baaf-211064f1ad8c" xlink:to="loc_us-gaap_RestrictedStockMember_019b0f49-2d1c-7269-b18b-e950af3cf88a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019c36eb-fe71-7677-ae76-648a7f1023d2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2d1c-7a56-baaf-211064f1ad8c" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019c36eb-fe71-7677-ae76-648a7f1023d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-7366-89fb-9d10daca46bb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportingUnitAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7e82-9b1a-24c6eba7eab8" xlink:to="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-7366-89fb-9d10daca46bb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7366-89fb-9d10daca46bb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-7366-89fb-9d10daca46bb" xlink:to="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7366-89fb-9d10daca46bb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7ab2-959c-a1da56f6616b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-7366-89fb-9d10daca46bb" xlink:to="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7ab2-959c-a1da56f6616b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyReportingUnitMember_019b0f49-2d1c-7fce-b4d7-38645ccda429" xlink:href="hcat-20251231.xsd#hcat_TechnologyReportingUnitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7ab2-959c-a1da56f6616b" xlink:to="loc_hcat_TechnologyReportingUnitMember_019b0f49-2d1c-7fce-b4d7-38645ccda429" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ProfessionalServicesReportingUnitMember_019b0f49-2d1c-75a7-90bc-f3f2281a4ae1" xlink:href="hcat-20251231.xsd#hcat_ProfessionalServicesReportingUnitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7ab2-959c-a1da56f6616b" xlink:to="loc_hcat_ProfessionalServicesReportingUnitMember_019b0f49-2d1c-75a7-90bc-f3f2281a4ae1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019c36eb-fe71-7701-aef8-6bb6b7eecf12" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7e82-9b1a-24c6eba7eab8" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019c36eb-fe71-7701-aef8-6bb6b7eecf12" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019c36eb-fe71-7701-aef8-6bb6b7eecf12_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019c36eb-fe71-7701-aef8-6bb6b7eecf12" xlink:to="loc_us-gaap_EquityComponentDomain_019c36eb-fe71-7701-aef8-6bb6b7eecf12_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019c36eb-fe71-7728-860f-4792d6dff81d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019c36eb-fe71-7701-aef8-6bb6b7eecf12" xlink:to="loc_us-gaap_EquityComponentDomain_019c36eb-fe71-7728-860f-4792d6dff81d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019c36eb-fe71-7780-99fc-d3ff9d4a5e88" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019c36eb-fe71-7728-860f-4792d6dff81d" xlink:to="loc_us-gaap_CommonStockMember_019c36eb-fe71-7780-99fc-d3ff9d4a5e88" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019b0f49-2d1c-77f4-877e-f1d325fca227" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019b0f49-2d1c-77f4-877e-f1d325fca227" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_019b0f49-2d1c-760c-a676-4c59952c8990" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_019b0f49-2d1c-760c-a676-4c59952c8990" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeFairValue1_019b0f49-2d1c-76f0-aa39-82c6a81477d4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeFairValue1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeFairValue1_019b0f49-2d1c-76f0-aa39-82c6a81477d4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_019b0f49-2d1c-7c5b-a85f-a1ccececbc35" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_019b0f49-2d1c-7c5b-a85f-a1ccececbc35" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_019b0f49-2d1c-7c83-8686-95285bfaef9b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_019b0f49-2d1c-7c83-8686-95285bfaef9b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessAcquisitionStockBasedCompensationSharesIssuableNumberOfShares_019b0f49-2d1c-7267-9fef-4e595aa48a24" xlink:href="hcat-20251231.xsd#hcat_BusinessAcquisitionStockBasedCompensationSharesIssuableNumberOfShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_hcat_BusinessAcquisitionStockBasedCompensationSharesIssuableNumberOfShares_019b0f49-2d1c-7267-9fef-4e595aa48a24" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_019b0f49-2d1c-7950-8e3d-7ec8129455f7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_019b0f49-2d1c-7950-8e3d-7ec8129455f7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessCombinationCashRetentionPayment_019b0f49-2d1c-73c7-80cd-66c23da9f6fd" xlink:href="hcat-20251231.xsd#hcat_BusinessCombinationCashRetentionPayment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_hcat_BusinessCombinationCashRetentionPayment_019b0f49-2d1c-73c7-80cd-66c23da9f6fd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan_019c36eb-fe71-73ad-a752-9b61b80a64c5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan_019c36eb-fe71-73ad-a752-9b61b80a64c5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeBenefitsAndShareBasedCompensation_019c36ec-e275-7b50-8421-716452bb41e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeBenefitsAndShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_EmployeeBenefitsAndShareBasedCompensation_019c36ec-e275-7b50-8421-716452bb41e6" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_019c36ed-16fe-7ae4-b500-edcf64ea1100" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_019c36ed-16fe-7ae4-b500-edcf64ea1100" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019b0f49-2d1c-7c8d-8aac-1f2f1a33b573" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_Goodwill_019b0f49-2d1c-7c8d-8aac-1f2f1a33b573" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_019b0f49-2d1c-78ca-9fdb-0993e2176e3e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_019b0f49-2d1c-78ca-9fdb-0993e2176e3e" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredTaxLiabilitiesAndGoodwill_019b0f49-2d1c-7f74-94e6-574489ab28a5" xlink:href="hcat-20251231.xsd#hcat_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredTaxLiabilitiesAndGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_hcat_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredTaxLiabilitiesAndGoodwill_019b0f49-2d1c-7f74-94e6-574489ab28a5" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_019b0f49-2d1c-7b39-a51a-2984cd68ccc2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-76fe-946a-2e28248508d9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_019b0f49-2d1c-7b39-a51a-2984cd68ccc2" xlink:type="arc" order="14"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/BusinessCombinationsScheduleofRecognizedIdentifiedAssetsAcquiredandLiabilitiesAssumedDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#BusinessCombinationsScheduleofRecognizedIdentifiedAssetsAcquiredandLiabilitiesAssumedDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/BusinessCombinationsScheduleofRecognizedIdentifiedAssetsAcquiredandLiabilitiesAssumedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-701e-a11a-f6a56767d5b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7801-8616-c0d83d060f24" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-701e-a11a-f6a56767d5b5" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7801-8616-c0d83d060f24" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7c7f-9069-e6e127887bc0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7801-8616-c0d83d060f24" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7c7f-9069-e6e127887bc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7c7f-9069-e6e127887bc0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7c7f-9069-e6e127887bc0" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7c7f-9069-e6e127887bc0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7a6f-93d8-31dcce6fb762" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-7c7f-9069-e6e127887bc0" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7a6f-93d8-31dcce6fb762" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_UpfrontHealthcareServicesMember_019c36ce-9b1f-7d45-996b-5c0d744c8cbd" xlink:href="hcat-20251231.xsd#hcat_UpfrontHealthcareServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7a6f-93d8-31dcce6fb762" xlink:to="loc_hcat_UpfrontHealthcareServicesMember_019c36ce-9b1f-7d45-996b-5c0d744c8cbd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_IntrapriseHealthLLC.Member_019b0f49-2d1c-742f-b9b4-cf842ebcad74" xlink:href="hcat-20251231.xsd#hcat_IntrapriseHealthLLC.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7a6f-93d8-31dcce6fb762" xlink:to="loc_hcat_IntrapriseHealthLLC.Member_019b0f49-2d1c-742f-b9b4-cf842ebcad74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_LumeonLtd.Member_019b0f49-2d1c-73fe-8e66-ae28879e4ced" xlink:href="hcat-20251231.xsd#hcat_LumeonLtd.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7a6f-93d8-31dcce6fb762" xlink:to="loc_hcat_LumeonLtd.Member_019b0f49-2d1c-73fe-8e66-ae28879e4ced" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CareviveSystemsInc.Member_019b0f49-2d1c-74d1-983a-73fcb010cfcd" xlink:href="hcat-20251231.xsd#hcat_CareviveSystemsInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7a6f-93d8-31dcce6fb762" xlink:to="loc_hcat_CareviveSystemsInc.Member_019b0f49-2d1c-74d1-983a-73fcb010cfcd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ERSCorporationMember_019b0f49-2d1c-70f3-bb05-d9076fb98469" xlink:href="hcat-20251231.xsd#hcat_ERSCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-7a6f-93d8-31dcce6fb762" xlink:to="loc_hcat_ERSCorporationMember_019b0f49-2d1c-70f3-bb05-d9076fb98469" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7e5d-b6ff-f5b2760a8478" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7801-8616-c0d83d060f24" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7e5d-b6ff-f5b2760a8478" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7e5d-b6ff-f5b2760a8478_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7e5d-b6ff-f5b2760a8478" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7e5d-b6ff-f5b2760a8478_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7193-bbd1-3046b44e9848" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7e5d-b6ff-f5b2760a8478" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7193-bbd1-3046b44e9848" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_019b0f49-2d1c-7d9c-8a2f-f7cc85469900" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7193-bbd1-3046b44e9848" xlink:to="loc_us-gaap_CustomerRelationshipsMember_019b0f49-2d1c-7d9c-8a2f-f7cc85469900" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7bac-b243-b1b87eda3743" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7193-bbd1-3046b44e9848" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7bac-b243-b1b87eda3743" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksMember_019b0f49-2d1c-77af-b648-9d7189f29ead" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TrademarksMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7193-bbd1-3046b44e9848" xlink:to="loc_us-gaap_TrademarksMember_019b0f49-2d1c-77af-b648-9d7189f29ead" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-701e-a11a-f6a56767d5b5" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_019b0f49-2d1c-7d13-8e2e-65a02673f9fc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_019b0f49-2d1c-7d13-8e2e-65a02673f9fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_019b0f49-2d1c-75bd-af11-7026a3873a99" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_019b0f49-2d1c-75bd-af11-7026a3873a99" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_019b0f49-2d1c-7d22-8221-416a637fbec8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_019b0f49-2d1c-7d22-8221-416a637fbec8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAssets_019c36ce-9b1f-7913-8bcb-125211d968f4" xlink:href="hcat-20251231.xsd#hcat_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:to="loc_hcat_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAssets_019c36ce-9b1f-7913-8bcb-125211d968f4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_019b0f49-2d1c-7b99-a82d-90dee96cf948" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_019b0f49-2d1c-7b99-a82d-90dee96cf948" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019b0f49-2d1c-758a-8250-b2e92eee8c6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019b0f49-2d1c-7bb3-b404-7dcc710a97cd" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019b0f49-2d1c-758a-8250-b2e92eee8c6c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019b0f49-2d1c-714f-91fb-6a2fb79fd434" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-701e-a11a-f6a56767d5b5" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019b0f49-2d1c-714f-91fb-6a2fb79fd434" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_019b0f49-2d1c-7679-ad9d-8b49eb09f586" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019b0f49-2d1c-714f-91fb-6a2fb79fd434" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_019b0f49-2d1c-7679-ad9d-8b49eb09f586" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue_019b0f49-2d1c-74a3-a53e-d73296d884dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019b0f49-2d1c-714f-91fb-6a2fb79fd434" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue_019b0f49-2d1c-74a3-a53e-d73296d884dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiability_019c36cf-836c-7465-980f-ac847122c621" xlink:href="hcat-20251231.xsd#hcat_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019b0f49-2d1c-714f-91fb-6a2fb79fd434" xlink:to="loc_hcat_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiability_019c36cf-836c-7465-980f-ac847122c621" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_019c36d4-3218-7326-9774-b8e0f3e9310e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019b0f49-2d1c-714f-91fb-6a2fb79fd434" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_019c36d4-3218-7326-9774-b8e0f3e9310e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019b0f49-2d1c-7860-aa4d-d888db8aa9c4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019b0f49-2d1c-714f-91fb-6a2fb79fd434" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019b0f49-2d1c-7860-aa4d-d888db8aa9c4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_019b0f49-2d1c-725e-a081-f83e1533aeac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-701e-a11a-f6a56767d5b5" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_019b0f49-2d1c-725e-a081-f83e1533aeac" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019b0f49-2d1c-7b41-99b3-aba994323281" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-701e-a11a-f6a56767d5b5" xlink:to="loc_us-gaap_Goodwill_019b0f49-2d1c-7b41-99b3-aba994323281" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_019b0f49-2d1c-7dbe-8749-b33e087e7e95" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-701e-a11a-f6a56767d5b5" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_019b0f49-2d1c-7dbe-8749-b33e087e7e95" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/BusinessCombinationsUnauditedProFormaFinancialInformationDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#BusinessCombinationsUnauditedProFormaFinancialInformationDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/BusinessCombinationsUnauditedProFormaFinancialInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-7b90-aa57-2d0b04043942" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7c31-b8c3-59a26290630f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-7b90-aa57-2d0b04043942" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7c31-b8c3-59a26290630f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-71b9-8d86-6b7d03902a0d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7c31-b8c3-59a26290630f" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-71b9-8d86-6b7d03902a0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-71b9-8d86-6b7d03902a0d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-71b9-8d86-6b7d03902a0d" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-71b9-8d86-6b7d03902a0d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-72e9-8671-5986fea23735" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-71b9-8d86-6b7d03902a0d" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-72e9-8671-5986fea23735" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_UpfrontAcquisitionMember_019c36ed-aae2-795e-8032-8de5729f46f5" xlink:href="hcat-20251231.xsd#hcat_UpfrontAcquisitionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-72e9-8671-5986fea23735" xlink:to="loc_hcat_UpfrontAcquisitionMember_019c36ed-aae2-795e-8032-8de5729f46f5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CareviveAndLumeonAcquisitionsMember_019b0f49-2d1c-7f5d-9552-aa3ef3804de1" xlink:href="hcat-20251231.xsd#hcat_CareviveAndLumeonAcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-72e9-8671-5986fea23735" xlink:to="loc_hcat_CareviveAndLumeonAcquisitionsMember_019b0f49-2d1c-7f5d-9552-aa3ef3804de1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonrecurringAdjustmentAxis_019b0f49-2d1c-78ba-9ea4-e67041b4422d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonrecurringAdjustmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019b0f49-2d1c-7c31-b8c3-59a26290630f" xlink:to="loc_us-gaap_NonrecurringAdjustmentAxis_019b0f49-2d1c-78ba-9ea4-e67041b4422d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonrecurringAdjustmentDomain_019b0f49-2d1c-78ba-9ea4-e67041b4422d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonrecurringAdjustmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_NonrecurringAdjustmentAxis_019b0f49-2d1c-78ba-9ea4-e67041b4422d" xlink:to="loc_us-gaap_NonrecurringAdjustmentDomain_019b0f49-2d1c-78ba-9ea4-e67041b4422d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonrecurringAdjustmentDomain_019b0f49-2d1c-7c46-915c-371df0e602e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonrecurringAdjustmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_NonrecurringAdjustmentAxis_019b0f49-2d1c-78ba-9ea4-e67041b4422d" xlink:to="loc_us-gaap_NonrecurringAdjustmentDomain_019b0f49-2d1c-7c46-915c-371df0e602e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_AmortizationOfAcquiredIntangibleAssetsMember_019b0f49-2d1c-79fa-bb02-8eac6b203530" xlink:href="hcat-20251231.xsd#hcat_AmortizationOfAcquiredIntangibleAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonrecurringAdjustmentDomain_019b0f49-2d1c-7c46-915c-371df0e602e6" xlink:to="loc_hcat_AmortizationOfAcquiredIntangibleAssetsMember_019b0f49-2d1c-79fa-bb02-8eac6b203530" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AcquisitionRelatedCostsMember_019b0f49-2d1c-7f6a-b6ff-291bd1caf232" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AcquisitionRelatedCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonrecurringAdjustmentDomain_019b0f49-2d1c-7c46-915c-371df0e602e6" xlink:to="loc_us-gaap_AcquisitionRelatedCostsMember_019b0f49-2d1c-7f6a-b6ff-291bd1caf232" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss_019b0f49-2d1c-7edc-8bcd-afd232775424" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019b0f49-2d1c-7b90-aa57-2d0b04043942" xlink:to="loc_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss_019b0f49-2d1c-7edc-8bcd-afd232775424" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/RevenueScheduleofRevenueDisaggregatedbyTypeofArrangementDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#RevenueScheduleofRevenueDisaggregatedbyTypeofArrangementDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/RevenueScheduleofRevenueDisaggregatedbyTypeofArrangementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_019b0f49-2d1c-7d4f-a896-f0ee77696a9e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7825-a30a-91907138b3ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019b0f49-2d1c-7d4f-a896-f0ee77696a9e" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7825-a30a-91907138b3ec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7629-bf6f-aa0f7c3967a9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7825-a30a-91907138b3ec" xlink:to="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7629-bf6f-aa0f7c3967a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7629-bf6f-aa0f7c3967a9_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7629-bf6f-aa0f7c3967a9" xlink:to="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7629-bf6f-aa0f7c3967a9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7cce-b00b-b2b45e7ad957" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019b0f49-2d1c-7629-bf6f-aa0f7c3967a9" xlink:to="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7cce-b00b-b2b45e7ad957" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_RecurringTechnologyMember_019b0f49-2d1c-74af-ac34-9c373332dcfa" xlink:href="hcat-20251231.xsd#hcat_RecurringTechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7cce-b00b-b2b45e7ad957" xlink:to="loc_hcat_RecurringTechnologyMember_019b0f49-2d1c-74af-ac34-9c373332dcfa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_OnetimeTechnologyMember_019b0f49-2d1c-7458-8efe-cbe9da1f930a" xlink:href="hcat-20251231.xsd#hcat_OnetimeTechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7cce-b00b-b2b45e7ad957" xlink:to="loc_hcat_OnetimeTechnologyMember_019b0f49-2d1c-7458-8efe-cbe9da1f930a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ProfessionalServicesMember_019b0f49-2d1c-744d-8486-da4d0a7a74b0" xlink:href="hcat-20251231.xsd#hcat_ProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b0f49-2d1c-7cce-b00b-b2b45e7ad957" xlink:to="loc_hcat_ProfessionalServicesMember_019b0f49-2d1c-744d-8486-da4d0a7a74b0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019b0f49-2d1c-7dce-a93a-bd5e6981a0dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019b0f49-2d1c-7d4f-a896-f0ee77696a9e" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019b0f49-2d1c-7dce-a93a-bd5e6981a0dc" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/RevenueNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#RevenueNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/RevenueNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_019b0f49-2d1c-7492-97db-17bb44f2a5a6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7d23-9808-b9c99003ecf6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019b0f49-2d1c-7492-97db-17bb44f2a5a6" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7d23-9808-b9c99003ecf6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019b0f49-2d1c-7974-b8db-4dce56de75e9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7d23-9808-b9c99003ecf6" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019b0f49-2d1c-7974-b8db-4dce56de75e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019b0f49-2d1c-7974-b8db-4dce56de75e9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019b0f49-2d1c-7974-b8db-4dce56de75e9" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019b0f49-2d1c-7974-b8db-4dce56de75e9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019b0f49-2d1c-7124-bfae-418958afa360" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019b0f49-2d1c-7974-b8db-4dce56de75e9" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019b0f49-2d1c-7124-bfae-418958afa360" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicConcentrationRiskMember_019b0f49-2d1c-78a9-8693-f1340f4c246f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019b0f49-2d1c-7124-bfae-418958afa360" xlink:to="loc_us-gaap_GeographicConcentrationRiskMember_019b0f49-2d1c-78a9-8693-f1340f4c246f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019b0f49-2d1c-76aa-9a00-adec2251bfb6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7d23-9808-b9c99003ecf6" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019b0f49-2d1c-76aa-9a00-adec2251bfb6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019b0f49-2d1c-76aa-9a00-adec2251bfb6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019b0f49-2d1c-76aa-9a00-adec2251bfb6" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019b0f49-2d1c-76aa-9a00-adec2251bfb6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019b0f49-2d1c-704a-a566-8a9468417fdd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019b0f49-2d1c-76aa-9a00-adec2251bfb6" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019b0f49-2d1c-704a-a566-8a9468417fdd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember_019b0f49-2d1c-79dd-a3cd-80bf8843077d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019b0f49-2d1c-704a-a566-8a9468417fdd" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerMember_019b0f49-2d1c-79dd-a3cd-80bf8843077d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019b0f49-2d1c-7f54-ae10-f309128b55b9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019b0f49-2d1c-7d23-9808-b9c99003ecf6" xlink:to="loc_srt_StatementGeographicalAxis_019b0f49-2d1c-7f54-ae10-f309128b55b9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019b0f49-2d1c-7f54-ae10-f309128b55b9_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019b0f49-2d1c-7f54-ae10-f309128b55b9" xlink:to="loc_srt_SegmentGeographicalDomain_019b0f49-2d1c-7f54-ae10-f309128b55b9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019b0f49-2d1c-768e-a22a-e936001e34c1" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019b0f49-2d1c-7f54-ae10-f309128b55b9" xlink:to="loc_srt_SegmentGeographicalDomain_019b0f49-2d1c-768e-a22a-e936001e34c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019b0f49-2d1c-71a2-9f12-da54b0ac88f0" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019b0f49-2d1c-768e-a22a-e936001e34c1" xlink:to="loc_country_US_019b0f49-2d1c-71a2-9f12-da54b0ac88f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019b0f49-2d1c-7e3a-a71e-18e4c3ecfde1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019b0f49-2d1c-7492-97db-17bb44f2a5a6" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019b0f49-2d1c-7e3a-a71e-18e4c3ecfde1" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/GoodwillandIntangibleAssetsScheduleofGoodwillbyReportingUnitDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#GoodwillandIntangibleAssetsScheduleofGoodwillbyReportingUnitDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/GoodwillandIntangibleAssetsScheduleofGoodwillbyReportingUnitDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_019b0f49-2d1c-7918-9ee6-d0dc52f8d319" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_019b0f49-2d1c-73bb-bad1-7fe3d30a04e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_019b0f49-2d1c-7918-9ee6-d0dc52f8d319" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_019b0f49-2d1c-73bb-bad1-7fe3d30a04e1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-71da-aa05-eed1ecde5a86" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportingUnitAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_019b0f49-2d1c-73bb-bad1-7fe3d30a04e1" xlink:to="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-71da-aa05-eed1ecde5a86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-71da-aa05-eed1ecde5a86_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-71da-aa05-eed1ecde5a86" xlink:to="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-71da-aa05-eed1ecde5a86_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7131-8643-1ff46eb134ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReportingUnitAxis_019b0f49-2d1c-71da-aa05-eed1ecde5a86" xlink:to="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7131-8643-1ff46eb134ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyMember_019b0f49-2d1c-7099-97cf-c8f2ce0f65ed" xlink:href="hcat-20251231.xsd#hcat_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7131-8643-1ff46eb134ab" xlink:to="loc_hcat_TechnologyMember_019b0f49-2d1c-7099-97cf-c8f2ce0f65ed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ProfessionalServicesMember_019b0f49-2d1c-76d4-a53c-2ca1df1ee826" xlink:href="hcat-20251231.xsd#hcat_ProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReportingUnitDomain_019b0f49-2d1c-7131-8643-1ff46eb134ab" xlink:to="loc_hcat_ProfessionalServicesMember_019b0f49-2d1c-76d4-a53c-2ca1df1ee826" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-735e-960b-986c22c2b3df" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_019b0f49-2d1c-73bb-bad1-7fe3d30a04e1" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-735e-960b-986c22c2b3df" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-735e-960b-986c22c2b3df_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-735e-960b-986c22c2b3df" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-735e-960b-986c22c2b3df_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-73b1-a75a-61cb1bd5dec7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2d1c-735e-960b-986c22c2b3df" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-73b1-a75a-61cb1bd5dec7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_IntrapriseHealthLLC.Member_019c3740-314c-766c-96ae-7b5788d3f398" xlink:href="hcat-20251231.xsd#hcat_IntrapriseHealthLLC.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-73b1-a75a-61cb1bd5dec7" xlink:to="loc_hcat_IntrapriseHealthLLC.Member_019c3740-314c-766c-96ae-7b5788d3f398" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_UpfrontAcquisitionMember_019c373f-82c5-7ebc-8137-cdeffee1cc39" xlink:href="hcat-20251231.xsd#hcat_UpfrontAcquisitionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2d1c-73b1-a75a-61cb1bd5dec7" xlink:to="loc_hcat_UpfrontAcquisitionMember_019c373f-82c5-7ebc-8137-cdeffee1cc39" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillRollForward_019b0f49-2d1c-76fc-9d40-113edead7e41" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_019b0f49-2d1c-7918-9ee6-d0dc52f8d319" xlink:to="loc_us-gaap_GoodwillRollForward_019b0f49-2d1c-76fc-9d40-113edead7e41" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019b0f49-2d1c-77c7-bbe5-c6e01fdbfd81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_019b0f49-2d1c-76fc-9d40-113edead7e41" xlink:to="loc_us-gaap_Goodwill_019b0f49-2d1c-77c7-bbe5-c6e01fdbfd81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAcquiredDuringPeriod_019b0f49-2d1c-77f3-b4fa-2d64979a21af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillAcquiredDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_019b0f49-2d1c-76fc-9d40-113edead7e41" xlink:to="loc_us-gaap_GoodwillAcquiredDuringPeriod_019b0f49-2d1c-77f3-b4fa-2d64979a21af" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_019c3740-c755-78b7-adc2-580502f1e0f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_019b0f49-2d1c-76fc-9d40-113edead7e41" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_019c3740-c755-78b7-adc2-580502f1e0f1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_019b105c-88ba-77b8-b987-abd78aa26ef1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_019b0f49-2d1c-76fc-9d40-113edead7e41" xlink:to="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_019b105c-88ba-77b8-b987-abd78aa26ef1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019b0f49-2d1c-7901-a5a8-af21da7a14e5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration_019cd37b-3a74-7869-835e-54e362fb9302" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillImpairmentLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_019b0f49-2d1c-7918-9ee6-d0dc52f8d319" xlink:to="loc_us-gaap_GoodwillImpairmentLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration_019cd37b-3a74-7869-835e-54e362fb9302" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b105f-bd26-7da9-8ad3-4078e49a1787" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b105f-bd26-71ec-8f99-37eede0748bf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b105f-bd26-7da9-8ad3-4078e49a1787" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b105f-bd26-71ec-8f99-37eede0748bf" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b105f-bd26-704f-8009-b230f54c5eae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b105f-bd26-71ec-8f99-37eede0748bf" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b105f-bd26-704f-8009-b230f54c5eae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-704f-8009-b230f54c5eae_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b105f-bd26-704f-8009-b230f54c5eae" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-704f-8009-b230f54c5eae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-7d18-a7a5-ce79083b8f2e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b105f-bd26-704f-8009-b230f54c5eae" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-7d18-a7a5-ce79083b8f2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_019b105f-bd26-7cb0-b072-d7e91998b11a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-7d18-a7a5-ce79083b8f2e" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_019b105f-bd26-7cb0-b072-d7e91998b11a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ClientRelationshipsAndContractsMember_019b105f-bd26-721c-901c-4e1aa071c599" xlink:href="hcat-20251231.xsd#hcat_ClientRelationshipsAndContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-7d18-a7a5-ce79083b8f2e" xlink:to="loc_hcat_ClientRelationshipsAndContractsMember_019b105f-bd26-721c-901c-4e1aa071c599" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_019b105f-bd26-7ddc-a292-f4f5c664532e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComputerSoftwareIntangibleAssetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-7d18-a7a5-ce79083b8f2e" xlink:to="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_019b105f-bd26-7ddc-a292-f4f5c664532e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksMember_019b105f-bd26-7bd2-a681-3fde0d09e863" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TrademarksMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b105f-bd26-7d18-a7a5-ce79083b8f2e" xlink:to="loc_us-gaap_TrademarksMember_019b105f-bd26-7bd2-a681-3fde0d09e863" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019b105f-bd26-74e3-923a-0cf25344b64d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b105f-bd26-7da9-8ad3-4078e49a1787" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019b105f-bd26-74e3-923a-0cf25344b64d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019b105f-bd26-7e94-bcfa-91bb6491ab7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b105f-bd26-7da9-8ad3-4078e49a1787" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019b105f-bd26-7e94-bcfa-91bb6491ab7e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019b105f-bd26-7177-9a57-3e503de35122" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b105f-bd26-7da9-8ad3-4078e49a1787" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019b105f-bd26-7177-9a57-3e503de35122" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/GoodwillandIntangibleAssetsScheduleofRemainingAmortizationPeriodDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#GoodwillandIntangibleAssetsScheduleofRemainingAmortizationPeriodDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/GoodwillandIntangibleAssetsScheduleofRemainingAmortizationPeriodDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b0f49-2d1c-7b1b-8fa6-927df15b1f9a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b0f49-2d1c-7558-abac-0a8ab2b1dd4e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b0f49-2d1c-7b1b-8fa6-927df15b1f9a" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b0f49-2d1c-7558-abac-0a8ab2b1dd4e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7570-9190-801d53b8a325" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019b0f49-2d1c-7558-abac-0a8ab2b1dd4e" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7570-9190-801d53b8a325" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7570-9190-801d53b8a325_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7570-9190-801d53b8a325" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7570-9190-801d53b8a325_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7244-b598-bc1133faf71f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019b0f49-2d1c-7570-9190-801d53b8a325" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7244-b598-bc1133faf71f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7d95-be9e-a859694e0f84" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7244-b598-bc1133faf71f" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_019b0f49-2d1c-7d95-be9e-a859694e0f84" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ClientRelationshipsAndContractsMember_019b0f49-2d1c-7162-9d44-0d66e1bb4bce" xlink:href="hcat-20251231.xsd#hcat_ClientRelationshipsAndContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7244-b598-bc1133faf71f" xlink:to="loc_hcat_ClientRelationshipsAndContractsMember_019b0f49-2d1c-7162-9d44-0d66e1bb4bce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_019b0f49-2d1c-7b62-b4d8-cdeaaf7410e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComputerSoftwareIntangibleAssetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7244-b598-bc1133faf71f" xlink:to="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_019b0f49-2d1c-7b62-b4d8-cdeaaf7410e2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksMember_019b0f49-2d1c-7410-8be0-f8a4cff69172" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TrademarksMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019b0f49-2d1c-7244-b598-bc1133faf71f" xlink:to="loc_us-gaap_TrademarksMember_019b0f49-2d1c-7410-8be0-f8a4cff69172" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_019b0f49-2d1c-73b4-8122-239f0764d970" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019b0f49-2d1c-7b1b-8fa6-927df15b1f9a" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_019b0f49-2d1c-73b4-8122-239f0764d970" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/PropertyandEquipmentScheduleofComponentsofPropertyandEquipmentDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#PropertyandEquipmentScheduleofComponentsofPropertyandEquipmentDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/PropertyandEquipmentScheduleofComponentsofPropertyandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7ad6-8c11-07ae2c7c1b6b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-74a3-a7d4-6fda91484d74" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7ad6-8c11-07ae2c7c1b6b" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-74a3-a7d4-6fda91484d74" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-75b3-ab3e-bb88878d5d2c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-74a3-a7d4-6fda91484d74" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-75b3-ab3e-bb88878d5d2c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-75b3-ab3e-bb88878d5d2c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-75b3-ab3e-bb88878d5d2c" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-75b3-ab3e-bb88878d5d2c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7ede-aeb7-24d692c5b096" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019b0f49-2d1c-75b3-ab3e-bb88878d5d2c" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7ede-aeb7-24d692c5b096" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerEquipmentMember_019b0f49-2d1c-7ee7-817f-dc0ad985da35" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComputerEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7ede-aeb7-24d692c5b096" xlink:to="loc_us-gaap_ComputerEquipmentMember_019b0f49-2d1c-7ee7-817f-dc0ad985da35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_019b0f49-2d1c-77e3-a5e4-3ced7f1d72fd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseholdImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7ede-aeb7-24d692c5b096" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_019b0f49-2d1c-77e3-a5e4-3ced7f1d72fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_019b0f49-2d1c-787a-830e-6c3502f3c14e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7ede-aeb7-24d692c5b096" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_019b0f49-2d1c-787a-830e-6c3502f3c14e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareDevelopmentMember_019b0f49-2d1c-7036-a37b-ebd249590d68" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SoftwareDevelopmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7ede-aeb7-24d692c5b096" xlink:to="loc_us-gaap_SoftwareDevelopmentMember_019b0f49-2d1c-7036-a37b-ebd249590d68" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019b0f49-2d1c-7150-8c2b-f68d9c51591f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019b0f49-2d1c-7ede-aeb7-24d692c5b096" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019b0f49-2d1c-7150-8c2b-f68d9c51591f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_019b0f49-2d1c-7c49-8c17-2321413aad91" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7ad6-8c11-07ae2c7c1b6b" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_019b0f49-2d1c-7c49-8c17-2321413aad91" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019b0f49-2d1c-740f-a645-4337a916b03d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7ad6-8c11-07ae2c7c1b6b" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019b0f49-2d1c-740f-a645-4337a916b03d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_019b0f49-2d1c-7dab-80be-3f7627de3229" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7ad6-8c11-07ae2c7c1b6b" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_019b0f49-2d1c-7dab-80be-3f7627de3229" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/PropertyandEquipmentNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#PropertyandEquipmentNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/PropertyandEquipmentNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7698-842a-68b7dd686b71" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7c9a-84e9-f797d32227b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7698-842a-68b7dd686b71" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7c9a-84e9-f797d32227b5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2d1c-7766-8d3b-52be56b97cf9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7c9a-84e9-f797d32227b5" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2d1c-7766-8d3b-52be56b97cf9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2d1c-7766-8d3b-52be56b97cf9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2d1c-7766-8d3b-52be56b97cf9" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2d1c-7766-8d3b-52be56b97cf9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2d1c-75ee-8cb1-1cecd4e85246" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2d1c-7766-8d3b-52be56b97cf9" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2d1c-75ee-8cb1-1cecd4e85246" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_LeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2d1c-7f2d-a2fb-3f20be5a3551" xlink:href="hcat-20251231.xsd#hcat_LeaseholdImprovementsAndFurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2d1c-75ee-8cb1-1cecd4e85246" xlink:to="loc_hcat_LeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2d1c-7f2d-a2fb-3f20be5a3551" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanAxis_019b0f49-2d1c-73bb-b79f-c5a69ddb6153" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019b0f49-2d1c-7c9a-84e9-f797d32227b5" xlink:to="loc_us-gaap_RestructuringPlanAxis_019b0f49-2d1c-73bb-b79f-c5a69ddb6153" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2d1c-73bb-b79f-c5a69ddb6153_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2d1c-73bb-b79f-c5a69ddb6153" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2d1c-73bb-b79f-c5a69ddb6153_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2d1c-7401-b602-006d3ccab66d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2d1c-73bb-b79f-c5a69ddb6153" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2d1c-7401-b602-006d3ccab66d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_A2023RestructuringPlanMember_019b0f49-2d1c-7114-9a4e-1f4c6759856f" xlink:href="hcat-20251231.xsd#hcat_A2023RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2d1c-7401-b602-006d3ccab66d" xlink:to="loc_hcat_A2023RestructuringPlanMember_019b0f49-2d1c-7114-9a4e-1f4c6759856f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation_019b0f49-2d1c-7eca-9e10-53e79889cd9a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Depreciation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7698-842a-68b7dd686b71" xlink:to="loc_us-gaap_Depreciation_019b0f49-2d1c-7eca-9e10-53e79889cd9a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseImpairmentLoss_019b0f49-2d1c-7600-85cc-33983ad889a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7698-842a-68b7dd686b71" xlink:to="loc_us-gaap_OperatingLeaseImpairmentLoss_019b0f49-2d1c-7600-85cc-33983ad889a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetImpairmentCharges_019b0f49-2d1c-7a35-a7f9-353b7c59f51e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7698-842a-68b7dd686b71" xlink:to="loc_us-gaap_AssetImpairmentCharges_019b0f49-2d1c-7a35-a7f9-353b7c59f51e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedComputerSoftwareNet_019b0f49-2d1c-7d0e-a612-4fb81763cd19" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedComputerSoftwareNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7698-842a-68b7dd686b71" xlink:to="loc_us-gaap_CapitalizedComputerSoftwareNet_019b0f49-2d1c-7d0e-a612-4fb81763cd19" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedComputerSoftwareAmortization1_019b0f49-2d1c-7eeb-808a-b0708766e1ea" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedComputerSoftwareAmortization1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019b0f49-2d1c-7698-842a-68b7dd686b71" xlink:to="loc_us-gaap_CapitalizedComputerSoftwareAmortization1_019b0f49-2d1c-7eeb-808a-b0708766e1ea" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/ShorttermInvestmentsScheduleofCashEquivalentsandShortTermInvestmentsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#ShorttermInvestmentsScheduleofCashEquivalentsandShortTermInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/ShorttermInvestmentsScheduleofCashEquivalentsandShortTermInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-78ef-90ba-0d595b12755a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019b0f49-2d1c-71e4-ab25-d0fc098b4acb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-78ef-90ba-0d595b12755a" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019b0f49-2d1c-71e4-ab25-d0fc098b4acb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-7f74-8f37-9ad172727710" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019b0f49-2d1c-71e4-ab25-d0fc098b4acb" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-7f74-8f37-9ad172727710" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7f74-8f37-9ad172727710_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-7f74-8f37-9ad172727710" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7f74-8f37-9ad172727710_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7228-8973-e83ee3756b64" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-7f74-8f37-9ad172727710" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7228-8973-e83ee3756b64" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MoneyMarketFundsMember_019b0f49-2d1c-7a01-a6d1-8577993f9408" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MoneyMarketFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7228-8973-e83ee3756b64" xlink:to="loc_us-gaap_MoneyMarketFundsMember_019b0f49-2d1c-7a01-a6d1-8577993f9408" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_019b0f49-2d1c-7175-a8f8-3ab6ad7e9033" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7228-8973-e83ee3756b64" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_019b0f49-2d1c-7175-a8f8-3ab6ad7e9033" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPaperMember_019b0f49-2d1c-73fe-aaba-844326f9c941" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommercialPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7228-8973-e83ee3756b64" xlink:to="loc_us-gaap_CommercialPaperMember_019b0f49-2d1c-73fe-aaba-844326f9c941" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateBondSecuritiesMember_019b0f49-2d1c-74a0-95fd-090f0f892645" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CorporateBondSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-7228-8973-e83ee3756b64" xlink:to="loc_us-gaap_CorporateBondSecuritiesMember_019b0f49-2d1c-74a0-95fd-090f0f892645" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7782-9dea-ff68e715ae80" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019b0f49-2d1c-71e4-ab25-d0fc098b4acb" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7782-9dea-ff68e715ae80" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-7782-9dea-ff68e715ae80_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7782-9dea-ff68e715ae80" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-7782-9dea-ff68e715ae80_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-76dc-8686-8a1d90f5efd9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7782-9dea-ff68e715ae80" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-76dc-8686-8a1d90f5efd9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsMember_019b0f49-2d1c-7748-befc-da8641ade1fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-76dc-8686-8a1d90f5efd9" xlink:to="loc_us-gaap_CashEquivalentsMember_019b0f49-2d1c-7748-befc-da8641ade1fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ShortTermMarketableSecurityMember_019b0f49-2d1c-7674-ae88-fe8620149986" xlink:href="hcat-20251231.xsd#hcat_ShortTermMarketableSecurityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-76dc-8686-8a1d90f5efd9" xlink:to="loc_hcat_ShortTermMarketableSecurityMember_019b0f49-2d1c-7674-ae88-fe8620149986" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019b0f49-2d1c-7cf8-8465-098c4de3aefa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-78ef-90ba-0d595b12755a" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019b0f49-2d1c-7cf8-8465-098c4de3aefa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019b0f49-2d1c-78b3-9a81-39643f04f1bc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-78ef-90ba-0d595b12755a" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019b0f49-2d1c-78b3-9a81-39643f04f1bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019b0f49-2d1c-7056-b0be-2934874fdc98" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-78ef-90ba-0d595b12755a" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019b0f49-2d1c-7056-b0be-2934874fdc98" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019b0f49-2d1c-7f1d-9f48-ece99178d365" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-78ef-90ba-0d595b12755a" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019b0f49-2d1c-7f1d-9f48-ece99178d365" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/ShorttermInvestmentsScheduleofShortTermInvestmentsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#ShorttermInvestmentsScheduleofShortTermInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/ShorttermInvestmentsScheduleofShortTermInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-7c52-af1b-8a964bf8b49f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019b0f49-2d1c-7496-9b41-2c5c50665090" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-7c52-af1b-8a964bf8b49f" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019b0f49-2d1c-7496-9b41-2c5c50665090" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7f7f-ae07-004ce32de789" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019b0f49-2d1c-7496-9b41-2c5c50665090" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7f7f-ae07-004ce32de789" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-7f7f-ae07-004ce32de789_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7f7f-ae07-004ce32de789" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-7f7f-ae07-004ce32de789_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-74f0-821d-06bdaee98553" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_019b0f49-2d1c-7f7f-ae07-004ce32de789" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-74f0-821d-06bdaee98553" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ShortTermMarketableSecurityMember_019b0f49-2d1c-759e-b3dd-f6bef46ba28c" xlink:href="hcat-20251231.xsd#hcat_ShortTermMarketableSecurityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_019b0f49-2d1c-74f0-821d-06bdaee98553" xlink:to="loc_hcat_ShortTermMarketableSecurityMember_019b0f49-2d1c-759e-b3dd-f6bef46ba28c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019b0f49-2d1c-74b8-8756-d967101090d9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-7c52-af1b-8a964bf8b49f" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019b0f49-2d1c-74b8-8756-d967101090d9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019b0f49-2d1c-7af9-bc14-dce379dce37f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019b0f49-2d1c-74b8-8756-d967101090d9" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019b0f49-2d1c-7af9-bc14-dce379dce37f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019b0f49-2d1c-76fc-b71d-e423d3462d6d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019b0f49-2d1c-74b8-8756-d967101090d9" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019b0f49-2d1c-76fc-b71d-e423d3462d6d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019b0f49-2d1c-7c4f-a783-b9dfef542484" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019b0f49-2d1c-74b8-8756-d967101090d9" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019b0f49-2d1c-7c4f-a783-b9dfef542484" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019b0f49-2d1c-7e86-ad5a-4577e0829ac5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019b0f49-2d1c-7c52-af1b-8a964bf8b49f" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019b0f49-2d1c-7e86-ad5a-4577e0829ac5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019b0f49-2d1c-7895-9e31-144eb4ce9ee6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019b0f49-2d1c-7e86-ad5a-4577e0829ac5" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019b0f49-2d1c-7895-9e31-144eb4ce9ee6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019b0f49-2d1c-7228-81bc-92cded6b5753" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019b0f49-2d1c-7e86-ad5a-4577e0829ac5" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019b0f49-2d1c-7228-81bc-92cded6b5753" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019b0f49-2d1c-7a4d-9e30-1b0afe97beb7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019b0f49-2d1c-7e86-ad5a-4577e0829ac5" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019b0f49-2d1c-7a4d-9e30-1b0afe97beb7" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsScheduleofFairValueofFinancialInstrumentsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#FairValueofFinancialInstrumentsScheduleofFairValueofFinancialInstrumentsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsScheduleofFairValueofFinancialInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7d3b-a175-6ef76ebe4c82" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2d1c-7702-aff1-265601348e4b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7d3b-a175-6ef76ebe4c82" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2d1c-7702-aff1-265601348e4b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-76a0-a390-48b1399c3a6e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2d1c-7702-aff1-265601348e4b" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-76a0-a390-48b1399c3a6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-76a0-a390-48b1399c3a6e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-76a0-a390-48b1399c3a6e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-76a0-a390-48b1399c3a6e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-775d-a11b-6ab596083204" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019b0f49-2d1c-76a0-a390-48b1399c3a6e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-775d-a11b-6ab596083204" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MoneyMarketFundsMember_019b0f49-2d1c-7f91-b449-5ca4256ece26" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MoneyMarketFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-775d-a11b-6ab596083204" xlink:to="loc_us-gaap_MoneyMarketFundsMember_019b0f49-2d1c-7f91-b449-5ca4256ece26" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_019b0f49-2d1c-721d-b3f6-f80616360540" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-775d-a11b-6ab596083204" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_019b0f49-2d1c-721d-b3f6-f80616360540" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPaperMember_019b0f49-2d1c-7399-b96f-46c981e734ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommercialPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-775d-a11b-6ab596083204" xlink:to="loc_us-gaap_CommercialPaperMember_019b0f49-2d1c-7399-b96f-46c981e734ba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateBondSecuritiesMember_019b0f49-2d1c-7800-b077-cefd3aec1c06" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CorporateBondSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019b0f49-2d1c-775d-a11b-6ab596083204" xlink:to="loc_us-gaap_CorporateBondSecuritiesMember_019b0f49-2d1c-7800-b077-cefd3aec1c06" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2d1c-73db-b6d7-e0a117eeee07" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2d1c-7702-aff1-265601348e4b" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2d1c-73db-b6d7-e0a117eeee07" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2d1c-73db-b6d7-e0a117eeee07_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2d1c-73db-b6d7-e0a117eeee07" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2d1c-73db-b6d7-e0a117eeee07_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2d1c-77f7-9541-979afdce88dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2d1c-73db-b6d7-e0a117eeee07" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2d1c-77f7-9541-979afdce88dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019b0f49-2d1c-73bd-a608-66abe1dd7225" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2d1c-77f7-9541-979afdce88dc" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019b0f49-2d1c-73bd-a608-66abe1dd7225" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019b0f49-2d1c-7475-afa4-c8b7fb6eda09" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2d1c-77f7-9541-979afdce88dc" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019b0f49-2d1c-7475-afa4-c8b7fb6eda09" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019b0f49-2d1c-7c2c-9907-4d209a2196e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2d1c-77f7-9541-979afdce88dc" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019b0f49-2d1c-7c2c-9907-4d209a2196e2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019c2ecf-523c-7d88-ab20-78d4439b74ca" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2d1c-7702-aff1-265601348e4b" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019c2ecf-523c-7d88-ab20-78d4439b74ca" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019c2ecf-523c-7d88-ab20-78d4439b74ca_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019c2ecf-523c-7d88-ab20-78d4439b74ca" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019c2ecf-523c-7d88-ab20-78d4439b74ca_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019c2ecf-523c-74b7-a8cc-60d6ee285a7c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019c2ecf-523c-7d88-ab20-78d4439b74ca" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019c2ecf-523c-74b7-a8cc-60d6ee285a7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019c2ecf-523c-7ea3-928a-bf716a45e842" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019c2ecf-523c-74b7-a8cc-60d6ee285a7c" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019c2ecf-523c-7ea3-928a-bf716a45e842" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019b0f49-2e0c-721f-9b8b-fb0dbf32983c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7d3b-a175-6ef76ebe4c82" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019b0f49-2e0c-721f-9b8b-fb0dbf32983c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019b0f49-2e0c-7848-900e-483241782f6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7d3b-a175-6ef76ebe4c82" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019b0f49-2e0c-7848-900e-483241782f6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_019b0f49-2e0c-7555-a5a6-3f5a5f8d5125" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7d3b-a175-6ef76ebe4c82" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_019b0f49-2e0c-7555-a5a6-3f5a5f8d5125" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueNetAssetLiability_019b0f49-2e0c-7e67-bea0-c2c273ba34b6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueNetAssetLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7d3b-a175-6ef76ebe4c82" xlink:to="loc_us-gaap_FairValueNetAssetLiability_019b0f49-2e0c-7e67-bea0-c2c273ba34b6" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#FairValueofFinancialInstrumentsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-7f97-8756-8f7d77b72198" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-7f97-8756-8f7d77b72198" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-792d-a857-8aefbdd4224d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-7f97-8756-8f7d77b72198" xlink:to="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-792d-a857-8aefbdd4224d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-792d-a857-8aefbdd4224d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-792d-a857-8aefbdd4224d" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-792d-a857-8aefbdd4224d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-72a7-a40b-8f38720d621d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-792d-a857-8aefbdd4224d" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-72a7-a40b-8f38720d621d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SeniorNotesDue2025Member_019b0f49-2e0c-767c-bcca-16caa262828c" xlink:href="hcat-20251231.xsd#hcat_SeniorNotesDue2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-72a7-a40b-8f38720d621d" xlink:to="loc_hcat_SeniorNotesDue2025Member_019b0f49-2e0c-767c-bcca-16caa262828c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-78fc-86fd-f588f945711f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-7f97-8756-8f7d77b72198" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-78fc-86fd-f588f945711f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-78fc-86fd-f588f945711f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-78fc-86fd-f588f945711f" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-78fc-86fd-f588f945711f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-77f9-a924-724f3ac1c61b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-78fc-86fd-f588f945711f" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-77f9-a924-724f3ac1c61b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_019b0f49-2e0c-76e3-a20c-7f7cb0f752d9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-77f9-a924-724f3ac1c61b" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_019b0f49-2e0c-76e3-a20c-7f7cb0f752d9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7f0a-accd-dfdd3d31b584" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-7f97-8756-8f7d77b72198" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7f0a-accd-dfdd3d31b584" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7f0a-accd-dfdd3d31b584_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7f0a-accd-dfdd3d31b584" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7f0a-accd-dfdd3d31b584_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7da2-a261-83c4a3f66238" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7f0a-accd-dfdd3d31b584" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7da2-a261-83c4a3f66238" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_UpfrontAcquisitionMember_019c3753-93cd-7676-8058-99015503c7fa" xlink:href="hcat-20251231.xsd#hcat_UpfrontAcquisitionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7da2-a261-83c4a3f66238" xlink:to="loc_hcat_UpfrontAcquisitionMember_019c3753-93cd-7676-8058-99015503c7fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-71f5-913e-fe7bebd8f5af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-7f97-8756-8f7d77b72198" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-71f5-913e-fe7bebd8f5af" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-71f5-913e-fe7bebd8f5af_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-71f5-913e-fe7bebd8f5af" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-71f5-913e-fe7bebd8f5af_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7761-8bea-301947e609f9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-71f5-913e-fe7bebd8f5af" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7761-8bea-301947e609f9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_RightOfUseAssetsLeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2e0c-7d3e-9099-9a77a20e0b1a" xlink:href="hcat-20251231.xsd#hcat_RightOfUseAssetsLeaseholdImprovementsAndFurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7761-8bea-301947e609f9" xlink:to="loc_hcat_RightOfUseAssetsLeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2e0c-7d3e-9099-9a77a20e0b1a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_019b0f49-2e0c-74fb-ada5-61e9c149d8c2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_019b0f49-2e0c-74fb-ada5-61e9c149d8c2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_019b0f49-2e0c-7f56-8986-ef586d342da7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_us-gaap_LongTermDebtFairValue_019b0f49-2e0c-7f56-8986-ef586d342da7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseImpairmentLoss_019b0f49-2e0c-7762-8fc0-698c3a03e880" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_us-gaap_OperatingLeaseImpairmentLoss_019b0f49-2e0c-7762-8fc0-698c3a03e880" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_019c7077-c2e3-7b6f-9526-6d86d9ed9fd3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_019c7077-c2e3-7b6f-9526-6d86d9ed9fd3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill_019cd24c-8a23-79c8-8688-e4c76d1cfe7f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill_019cd24c-8a23-79c8-8688-e4c76d1cfe7f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh_019b0f49-2e0c-74ae-b41f-1b8677c626d8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh_019b0f49-2e0c-74ae-b41f-1b8677c626d8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessCombinationConsiderationTransferredEquityInterestsPaidForEquitySharesPercentage_019c3753-dce7-7ef3-bd87-6f336fcf49fa" xlink:href="hcat-20251231.xsd#hcat_BusinessCombinationConsiderationTransferredEquityInterestsPaidForEquitySharesPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_hcat_BusinessCombinationConsiderationTransferredEquityInterestsPaidForEquitySharesPercentage_019c3753-dce7-7ef3-bd87-6f336fcf49fa" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessCombinationConsiderationTransferredCashPaidPercentage_019c3754-1ed7-7ee7-941f-445d16cbc613" xlink:href="hcat-20251231.xsd#hcat_BusinessCombinationConsiderationTransferredCashPaidPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-777f-b4d7-039dbacff083" xlink:to="loc_hcat_BusinessCombinationConsiderationTransferredCashPaidPercentage_019c3754-1ed7-7ee7-941f-445d16cbc613" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsScheduleofContingentConsiderationLiabilitiesDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#FairValueofFinancialInstrumentsScheduleofContingentConsiderationLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsScheduleofContingentConsiderationLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-791f-bbf2-00ef53b34720" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-78c4-bec2-830a93e90f47" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-791f-bbf2-00ef53b34720" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-78c4-bec2-830a93e90f47" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-768c-adb8-113806367b3f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-78c4-bec2-830a93e90f47" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-768c-adb8-113806367b3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-768c-adb8-113806367b3f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-768c-adb8-113806367b3f" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-768c-adb8-113806367b3f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-75e4-bb60-111203d1fd05" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-768c-adb8-113806367b3f" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-75e4-bb60-111203d1fd05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019b0f49-2e0c-7a70-8076-f83fbf61407c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-75e4-bb60-111203d1fd05" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019b0f49-2e0c-7a70-8076-f83fbf61407c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0c-7a3b-aaed-3bd520e653b4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-78c4-bec2-830a93e90f47" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0c-7a3b-aaed-3bd520e653b4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-7a3b-aaed-3bd520e653b4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0c-7a3b-aaed-3bd520e653b4" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-7a3b-aaed-3bd520e653b4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-779c-803a-36a8e1ad7e9f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0c-7a3b-aaed-3bd520e653b4" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-779c-803a-36a8e1ad7e9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputQuotedPriceMember_019b0f49-2e0c-70b2-b36e-32c76c0a42aa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputQuotedPriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-779c-803a-36a8e1ad7e9f" xlink:to="loc_us-gaap_MeasurementInputQuotedPriceMember_019b0f49-2e0c-70b2-b36e-32c76c0a42aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputRevenueMultipleMember_019b0f49-2e0c-77f1-8832-d5418038279f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputRevenueMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-779c-803a-36a8e1ad7e9f" xlink:to="loc_us-gaap_MeasurementInputRevenueMultipleMember_019b0f49-2e0c-77f1-8832-d5418038279f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputExpectedTermMember_019b0f49-2e0c-731a-aa1a-6b37b39c237d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputExpectedTermMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-779c-803a-36a8e1ad7e9f" xlink:to="loc_us-gaap_MeasurementInputExpectedTermMember_019b0f49-2e0c-731a-aa1a-6b37b39c237d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputRiskFreeInterestRateMember_019b0f49-2e0c-713c-b4b2-7648180aab50" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputRiskFreeInterestRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0c-779c-803a-36a8e1ad7e9f" xlink:to="loc_us-gaap_MeasurementInputRiskFreeInterestRateMember_019b0f49-2e0c-713c-b4b2-7648180aab50" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7561-8a7f-59a1ee7d30b0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-78c4-bec2-830a93e90f47" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7561-8a7f-59a1ee7d30b0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7561-8a7f-59a1ee7d30b0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7561-8a7f-59a1ee7d30b0" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7561-8a7f-59a1ee7d30b0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7481-b0a3-d0bb79e51192" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-7561-8a7f-59a1ee7d30b0" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7481-b0a3-d0bb79e51192" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CareviveAndLumeonAcquisitionsMember_019b0f49-2e0c-7a25-ae44-5f4df992b085" xlink:href="hcat-20251231.xsd#hcat_CareviveAndLumeonAcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7481-b0a3-d0bb79e51192" xlink:to="loc_hcat_CareviveAndLumeonAcquisitionsMember_019b0f49-2e0c-7a25-ae44-5f4df992b085" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_019b0f49-2e0c-788f-a772-7eb18a9711f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-78c4-bec2-830a93e90f47" xlink:to="loc_us-gaap_ValuationTechniqueAxis_019b0f49-2e0c-788f-a772-7eb18a9711f4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019b0f49-2e0c-788f-a772-7eb18a9711f4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019b0f49-2e0c-788f-a772-7eb18a9711f4" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019b0f49-2e0c-788f-a772-7eb18a9711f4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019b0f49-2e0c-71e4-a05b-b54afa8bf6b4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019b0f49-2e0c-788f-a772-7eb18a9711f4" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019b0f49-2e0c-71e4-a05b-b54afa8bf6b4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ValuationMonteCarloMember_019c3759-5625-70e0-862f-4851c1b86116" xlink:href="hcat-20251231.xsd#hcat_ValuationMonteCarloMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019b0f49-2e0c-71e4-a05b-b54afa8bf6b4" xlink:to="loc_hcat_ValuationMonteCarloMember_019c3759-5625-70e0-862f-4851c1b86116" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput_019b0f49-2e0c-7610-b92b-63ef10e7757e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-791f-bbf2-00ef53b34720" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput_019b0f49-2e0c-7610-b92b-63ef10e7757e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsScheduleofContingentConsiderationDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#FairValueofFinancialInstrumentsScheduleofContingentConsiderationDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/FairValueofFinancialInstrumentsScheduleofContingentConsiderationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7508-8d0a-62a99b665337" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-738a-91a3-1c380f40a605" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7508-8d0a-62a99b665337" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-738a-91a3-1c380f40a605" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByLiabilityClassAxis_019b0f49-2e0c-7dc3-9860-30abf2f7902f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByLiabilityClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-738a-91a3-1c380f40a605" xlink:to="loc_us-gaap_FairValueByLiabilityClassAxis_019b0f49-2e0c-7dc3-9860-30abf2f7902f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019b0f49-2e0c-7dc3-9860-30abf2f7902f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019b0f49-2e0c-7dc3-9860-30abf2f7902f" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019b0f49-2e0c-7dc3-9860-30abf2f7902f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019b0f49-2e0c-73a6-a836-25812ecc7b46" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019b0f49-2e0c-7dc3-9860-30abf2f7902f" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019b0f49-2e0c-73a6-a836-25812ecc7b46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ContingentConsiderationLiabilityMember_019b0f49-2e0c-7410-928f-4cc44bd25692" xlink:href="hcat-20251231.xsd#hcat_ContingentConsiderationLiabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019b0f49-2e0c-73a6-a836-25812ecc7b46" xlink:to="loc_hcat_ContingentConsiderationLiabilityMember_019b0f49-2e0c-7410-928f-4cc44bd25692" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-7a0c-891f-0a1d4bb51db8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-738a-91a3-1c380f40a605" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-7a0c-891f-0a1d4bb51db8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-7a0c-891f-0a1d4bb51db8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-7a0c-891f-0a1d4bb51db8" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-7a0c-891f-0a1d4bb51db8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-761a-8b32-1c3e33972849" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019b0f49-2e0c-7a0c-891f-0a1d4bb51db8" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-761a-8b32-1c3e33972849" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019b0f49-2e0c-7f02-b6c8-f606274883c2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019b0f49-2e0c-761a-8b32-1c3e33972849" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019b0f49-2e0c-7f02-b6c8-f606274883c2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-74fc-97c1-afd34821f88a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019b0f49-2e0c-738a-91a3-1c380f40a605" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-74fc-97c1-afd34821f88a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-74fc-97c1-afd34821f88a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-74fc-97c1-afd34821f88a" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-74fc-97c1-afd34821f88a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-74de-ac19-36b2aa06489d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-74fc-97c1-afd34821f88a" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-74de-ac19-36b2aa06489d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CareviveAndLumeonAcquisitionsMember_019b0f49-2e0c-747b-ba4d-96f02deb91e1" xlink:href="hcat-20251231.xsd#hcat_CareviveAndLumeonAcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-74de-ac19-36b2aa06489d" xlink:to="loc_hcat_CareviveAndLumeonAcquisitionsMember_019b0f49-2e0c-747b-ba4d-96f02deb91e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019b0f49-2e0c-72ff-a289-bbd0514795a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_019b0f49-2e0c-7508-8d0a-62a99b665337" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019b0f49-2e0c-72ff-a289-bbd0514795a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019b0f49-2e0c-7928-a4aa-1a1211400524" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019b0f49-2e0c-72ff-a289-bbd0514795a7" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019b0f49-2e0c-7928-a4aa-1a1211400524" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases_019b0f49-2e0c-791a-80c9-bf85ded7d7bd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019b0f49-2e0c-72ff-a289-bbd0514795a7" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases_019b0f49-2e0c-791a-80c9-bf85ded7d7bd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_019b0f49-2e0c-76a3-a574-d5265d7933a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019b0f49-2e0c-72ff-a289-bbd0514795a7" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_019b0f49-2e0c-76a3-a574-d5265d7933a5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019b0f49-2e0c-793e-8614-5118d6f41d75" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/LeasesNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#LeasesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/LeasesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeLeaseDescriptionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeLeaseDescriptionTable_019b0f49-2e0c-7eb4-8950-9bf0bdeabad3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeLeaseDescriptionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_us-gaap_LesseeLeaseDescriptionTable_019b0f49-2e0c-7eb4-8950-9bf0bdeabad3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b0f49-2e0c-786e-b104-8adaa9817d22" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_019b0f49-2e0c-7eb4-8950-9bf0bdeabad3" xlink:to="loc_srt_RangeAxis_019b0f49-2e0c-786e-b104-8adaa9817d22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0c-786e-b104-8adaa9817d22_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b0f49-2e0c-786e-b104-8adaa9817d22" xlink:to="loc_srt_RangeMember_019b0f49-2e0c-786e-b104-8adaa9817d22_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0c-70c4-ba05-145e8e2cc2ec" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b0f49-2e0c-786e-b104-8adaa9817d22" xlink:to="loc_srt_RangeMember_019b0f49-2e0c-70c4-ba05-145e8e2cc2ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b0f49-2e0c-75e9-8810-88ff02aef2b9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0c-70c4-ba05-145e8e2cc2ec" xlink:to="loc_srt_MinimumMember_019b0f49-2e0c-75e9-8810-88ff02aef2b9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b0f49-2e0c-7778-bc3b-d5b317ad3b2e" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0c-70c4-ba05-145e8e2cc2ec" xlink:to="loc_srt_MaximumMember_019b0f49-2e0c-7778-bc3b-d5b317ad3b2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-7456-97d3-3f11039fb637" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_019b0f49-2e0c-7eb4-8950-9bf0bdeabad3" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-7456-97d3-3f11039fb637" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7456-97d3-3f11039fb637_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-7456-97d3-3f11039fb637" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7456-97d3-3f11039fb637_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7f94-95aa-8b15529e9e1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis_019b0f49-2e0c-7456-97d3-3f11039fb637" xlink:to="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7f94-95aa-8b15529e9e1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CorporateHeadquartersMember_019b0f49-2e0c-783d-8f92-4c7778704261" xlink:href="hcat-20251231.xsd#hcat_CorporateHeadquartersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7f94-95aa-8b15529e9e1e" xlink:to="loc_hcat_CorporateHeadquartersMember_019b0f49-2e0c-783d-8f92-4c7778704261" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_RightOfUseAssetsLeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2e0c-7617-af3c-2e7b9f781d26" xlink:href="hcat-20251231.xsd#hcat_RightOfUseAssetsLeaseholdImprovementsAndFurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7f94-95aa-8b15529e9e1e" xlink:to="loc_hcat_RightOfUseAssetsLeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2e0c-7617-af3c-2e7b9f781d26" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_RightOfUseAssetMember_019b0f49-2e0c-77cf-b8c9-6d1d7c3c19ae" xlink:href="hcat-20251231.xsd#hcat_RightOfUseAssetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7f94-95aa-8b15529e9e1e" xlink:to="loc_hcat_RightOfUseAssetMember_019b0f49-2e0c-77cf-b8c9-6d1d7c3c19ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_LeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2e0c-757a-84de-5f939480db53" xlink:href="hcat-20251231.xsd#hcat_LeaseholdImprovementsAndFurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ImpairedLongLivedAssetsHeldAndUsedAssetNameDomain_019b0f49-2e0c-7f94-95aa-8b15529e9e1e" xlink:to="loc_hcat_LeaseholdImprovementsAndFurnitureAndFixturesMember_019b0f49-2e0c-757a-84de-5f939480db53" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_019b0f49-2e0c-77dd-b230-96cfc1af60c5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseRenewalTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_us-gaap_LesseeOperatingLeaseRenewalTerm_019b0f49-2e0c-77dd-b230-96cfc1af60c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetRentableArea_019b0f49-2e0c-709c-85f3-cd26cdaf032d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetRentableArea"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_us-gaap_NetRentableArea_019b0f49-2e0c-709c-85f3-cd26cdaf032d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_019b0f49-2e0c-70be-807a-8ed58d65ea44" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_us-gaap_OperatingLeaseLiability_019b0f49-2e0c-70be-807a-8ed58d65ea44" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_019b0f49-2e0c-7108-9a89-79c38ec451a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_019b0f49-2e0c-7108-9a89-79c38ec451a9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SubleasedRentableArea_019b0f49-2e0c-7554-ae55-f3b1decdf8c9" xlink:href="hcat-20251231.xsd#hcat_SubleasedRentableArea"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_hcat_SubleasedRentableArea_019b0f49-2e0c-7554-ae55-f3b1decdf8c9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_LessorOperatingLeaseSubleaseLeaseTerm_019b0f49-2e0c-7b2b-94fd-f072362ca415" xlink:href="hcat-20251231.xsd#hcat_LessorOperatingLeaseSubleaseLeaseTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_hcat_LessorOperatingLeaseSubleaseLeaseTerm_019b0f49-2e0c-7b2b-94fd-f072362ca415" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseImpairmentLoss_019b0f49-2e0c-7d31-8bf8-fad2f3269b87" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_019b0f49-2e0c-7b63-8b21-67c710ad2de8" xlink:to="loc_us-gaap_OperatingLeaseImpairmentLoss_019b0f49-2e0c-7d31-8bf8-fad2f3269b87" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/DebtScheduleofDebtDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#DebtScheduleofDebtDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/DebtScheduleofDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_019b0f49-2e0c-74f0-9c82-d1973e1ce205" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_019b0f49-2e0c-74f0-9c82-d1973e1ce205" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-7cfe-a1f7-e20c23349925" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019b0f49-2e0c-74f0-9c82-d1973e1ce205" xlink:to="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-7cfe-a1f7-e20c23349925" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-7cfe-a1f7-e20c23349925_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-7cfe-a1f7-e20c23349925" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-7cfe-a1f7-e20c23349925_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-702c-813c-1836315b5e76" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019b0f49-2e0c-7cfe-a1f7-e20c23349925" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-702c-813c-1836315b5e76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_InterestRateTermLoanMember_019b0f49-2e0c-78f2-a158-4f4d50fe2775" xlink:href="hcat-20251231.xsd#hcat_InterestRateTermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-702c-813c-1836315b5e76" xlink:to="loc_hcat_InterestRateTermLoanMember_019b0f49-2e0c-78f2-a158-4f4d50fe2775" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SeniorNotesDue2025Member_019b0f49-2e0c-7c26-b145-de872034403f" xlink:href="hcat-20251231.xsd#hcat_SeniorNotesDue2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019b0f49-2e0c-702c-813c-1836315b5e76" xlink:to="loc_hcat_SeniorNotesDue2025Member_019b0f49-2e0c-7c26-b145-de872034403f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7249-bb7d-7a96d741df4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019b0f49-2e0c-74f0-9c82-d1973e1ce205" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7249-bb7d-7a96d741df4c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-7249-bb7d-7a96d741df4c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7249-bb7d-7a96d741df4c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-7249-bb7d-7a96d741df4c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-7a43-a36e-cbec467faaf5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7249-bb7d-7a96d741df4c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-7a43-a36e-cbec467faaf5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_019b0f49-2e0c-72ab-b07e-d0c255b47664" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-7a43-a36e-cbec467faaf5" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_019b0f49-2e0c-72ab-b07e-d0c255b47664" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019b0f49-2e0c-7ead-a861-87dbe2521579" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019b0f49-2e0c-7ead-a861-87dbe2521579" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019b0f49-2e0c-7bc3-a7e5-f487572600dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019b0f49-2e0c-7bc3-a7e5-f487572600dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_019b0f49-2e0c-7735-88bb-5a5b0b0be6fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_019b0f49-2e0c-7735-88bb-5a5b0b0be6fa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_019b0f49-2e0c-73ae-845f-246d4aeea318" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:to="loc_us-gaap_LongTermDebt_019b0f49-2e0c-73ae-845f-246d4aeea318" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_019b0f49-2e0c-71f6-bf16-88e9b98ee0e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:to="loc_us-gaap_LongTermDebtCurrent_019b0f49-2e0c-71f6-bf16-88e9b98ee0e1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_019b0f49-2e0c-72b7-9ab5-44d7c3c5b3e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-797b-88a6-efa7a4183494" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_019b0f49-2e0c-72b7-9ab5-44d7c3c5b3e7" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/DebtScheduleofComponentsofInterestExpenseDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#DebtScheduleofComponentsofInterestExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/DebtScheduleofComponentsofInterestExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-7f0b-be72-920a9c4b104c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_019b0f49-2e0c-7a36-8642-f044c4888676" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-7f0b-be72-920a9c4b104c" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_019b0f49-2e0c-7a36-8642-f044c4888676" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7515-8425-6723f3d6e28c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019b0f49-2e0c-7a36-8642-f044c4888676" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7515-8425-6723f3d6e28c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-7515-8425-6723f3d6e28c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7515-8425-6723f3d6e28c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-7515-8425-6723f3d6e28c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-72f2-b605-f03b24debe6d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019b0f49-2e0c-7515-8425-6723f3d6e28c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-72f2-b605-f03b24debe6d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_019b0f49-2e0c-7a45-9d45-fa79df022cc3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019b0f49-2e0c-72f2-b605-f03b24debe6d" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_019b0f49-2e0c-7a45-9d45-fa79df022cc3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_019b0f49-2e0c-7684-b651-d5db01e07630" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-7f0b-be72-920a9c4b104c" xlink:to="loc_us-gaap_InterestExpenseDebt_019b0f49-2e0c-7684-b651-d5db01e07630" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_019b0f49-2e0c-7519-bff6-59252831ed96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-7f0b-be72-920a9c4b104c" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_019b0f49-2e0c-7519-bff6-59252831ed96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_019b0f49-2e0c-75f4-aa53-325ca8b56c9d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-7f0b-be72-920a9c4b104c" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_019b0f49-2e0c-75f4-aa53-325ca8b56c9d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpense_019b0f49-2e0c-71e0-98c5-86fffedd7395" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019b0f49-2e0c-7f0b-be72-920a9c4b104c" xlink:to="loc_us-gaap_InterestExpense_019b0f49-2e0c-71e0-98c5-86fffedd7395" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/DebtNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#DebtNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/DebtNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019c376c-db25-7540-b6d8-bbb548389c46" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:to="loc_us-gaap_DebtInstrumentAxis_019c376c-db25-7540-b6d8-bbb548389c46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019c376c-db25-7540-b6d8-bbb548389c46_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019c376c-db25-7540-b6d8-bbb548389c46" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019c376c-db25-7540-b6d8-bbb548389c46_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019c376c-db25-726f-ab25-a4a7ecc57c43" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019c376c-db25-7540-b6d8-bbb548389c46" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019c376c-db25-726f-ab25-a4a7ecc57c43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CreditAgreementMember_019c376c-db25-7fb3-8e51-99882953c088" xlink:href="hcat-20251231.xsd#hcat_CreditAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019c376c-db25-726f-ab25-a4a7ecc57c43" xlink:to="loc_hcat_CreditAgreementMember_019c376c-db25-7fb3-8e51-99882953c088" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SeniorNotesDue2025Member_019c376c-db25-7f87-8137-4384e20d2666" xlink:href="hcat-20251231.xsd#hcat_SeniorNotesDue2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019c376c-db25-726f-ab25-a4a7ecc57c43" xlink:to="loc_hcat_SeniorNotesDue2025Member_019c376c-db25-7f87-8137-4384e20d2666" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019c376c-db25-7e57-8770-96091f67efae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019c376c-db25-7e57-8770-96091f67efae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019c376c-db25-7e57-8770-96091f67efae_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019c376c-db25-7e57-8770-96091f67efae" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019c376c-db25-7e57-8770-96091f67efae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019c376c-db25-7cde-a6c5-037cb0637f5b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019c376c-db25-7e57-8770-96091f67efae" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019c376c-db25-7cde-a6c5-037cb0637f5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TermLoanMember_019c376c-db25-7fe7-a72b-95bd4c9367dd" xlink:href="hcat-20251231.xsd#hcat_TermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019c376c-db25-7cde-a6c5-037cb0637f5b" xlink:to="loc_hcat_TermLoanMember_019c376c-db25-7fe7-a72b-95bd4c9367dd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DelayedDrawTermLoanMember_019c376c-db25-7f4e-8290-aefe70f7e3b8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DelayedDrawTermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019c376c-db25-7cde-a6c5-037cb0637f5b" xlink:to="loc_us-gaap_DelayedDrawTermLoanMember_019c376c-db25-7f4e-8290-aefe70f7e3b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_019c376c-db25-7484-9a1d-f3c60689d92a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019c376c-db25-7cde-a6c5-037cb0637f5b" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_019c376c-db25-7484-9a1d-f3c60689d92a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019c376c-db25-70d4-b682-6ec21e27b428" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:to="loc_us-gaap_CreditFacilityAxis_019c376c-db25-70d4-b682-6ec21e27b428" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019c376c-db25-70d4-b682-6ec21e27b428_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019c376c-db25-70d4-b682-6ec21e27b428" xlink:to="loc_us-gaap_CreditFacilityDomain_019c376c-db25-70d4-b682-6ec21e27b428_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019c376c-db25-75a7-9fcf-ffc87dfc5e2a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019c376c-db25-70d4-b682-6ec21e27b428" xlink:to="loc_us-gaap_CreditFacilityDomain_019c376c-db25-75a7-9fcf-ffc87dfc5e2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019c376c-db25-7a75-a30c-3cf10be35667" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019c376c-db25-75a7-9fcf-ffc87dfc5e2a" xlink:to="loc_us-gaap_LineOfCreditMember_019c376c-db25-7a75-a30c-3cf10be35667" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019c376c-db25-7717-9d07-a98542b46b13" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:to="loc_srt_RangeAxis_019c376c-db25-7717-9d07-a98542b46b13" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019c376c-db25-7717-9d07-a98542b46b13_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019c376c-db25-7717-9d07-a98542b46b13" xlink:to="loc_srt_RangeMember_019c376c-db25-7717-9d07-a98542b46b13_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019c376c-db25-7102-a3fa-1f3dcecab129" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019c376c-db25-7717-9d07-a98542b46b13" xlink:to="loc_srt_RangeMember_019c376c-db25-7102-a3fa-1f3dcecab129" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019c376c-db25-72c3-b051-bd0ee75a05a1" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019c376c-db25-7102-a3fa-1f3dcecab129" xlink:to="loc_srt_MinimumMember_019c376c-db25-72c3-b051-bd0ee75a05a1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019c376c-db25-7316-9b5a-4ff1ea168b4c" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019c376c-db25-7102-a3fa-1f3dcecab129" xlink:to="loc_srt_MaximumMember_019c376c-db25-7316-9b5a-4ff1ea168b4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019cd740-ee69-70e8-90c0-10747adaf2ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019cd740-ee69-70e8-90c0-10747adaf2ba" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019cd740-ee69-70e8-90c0-10747adaf2ba_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019cd740-ee69-70e8-90c0-10747adaf2ba" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019cd740-ee69-70e8-90c0-10747adaf2ba_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019cd740-ee69-70a5-bd7f-5b3e95b2f677" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019cd740-ee69-70e8-90c0-10747adaf2ba" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019cd740-ee69-70a5-bd7f-5b3e95b2f677" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CappedCallMember_019cd740-ee69-739a-bee0-1b664ba83e2d" xlink:href="hcat-20251231.xsd#hcat_CappedCallMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019cd740-ee69-70a5-bd7f-5b3e95b2f677" xlink:to="loc_hcat_CappedCallMember_019cd740-ee69-739a-bee0-1b664ba83e2d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019cd740-ee69-7fb1-8a25-306111fb1eb4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019cd740-ee69-7fb1-8a25-306111fb1eb4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019cd740-ee69-7fb1-8a25-306111fb1eb4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019cd740-ee69-7fb1-8a25-306111fb1eb4" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019cd740-ee69-7fb1-8a25-306111fb1eb4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019cd740-ee69-730e-976d-28b071137900" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019cd740-ee69-7fb1-8a25-306111fb1eb4" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019cd740-ee69-730e-976d-28b071137900" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019cd740-ee69-7c0b-b89e-b57e8f80f7a4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019cd740-ee69-730e-976d-28b071137900" xlink:to="loc_us-gaap_CashFlowHedgingMember_019cd740-ee69-7c0b-b89e-b57e8f80f7a4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019cd740-ee69-770c-875e-6cfbb110d13c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019c376c-db25-7920-9b2b-206bd8632a44" xlink:to="loc_us-gaap_HedgingDesignationAxis_019cd740-ee69-770c-875e-6cfbb110d13c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019cd740-ee69-770c-875e-6cfbb110d13c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019cd740-ee69-770c-875e-6cfbb110d13c" xlink:to="loc_us-gaap_HedgingDesignationDomain_019cd740-ee69-770c-875e-6cfbb110d13c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019cd740-ee69-791b-9829-1e66ff6e8807" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019cd740-ee69-770c-875e-6cfbb110d13c" xlink:to="loc_us-gaap_HedgingDesignationDomain_019cd740-ee69-791b-9829-1e66ff6e8807" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019cd740-ee69-739e-a738-a6c0a6e413f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019cd740-ee69-791b-9829-1e66ff6e8807" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019cd740-ee69-739e-a738-a6c0a6e413f8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTerm_019c376c-db25-7bd9-8d90-4e08e26dfe90" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_DebtInstrumentTerm_019c376c-db25-7bd9-8d90-4e08e26dfe90" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019c376c-db25-724c-a4a5-a64cd607d932" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019c376c-db25-724c-a4a5-a64cd607d932" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_019c376c-db25-7ed0-a85a-de3132b56f95" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_019c376c-db25-7ed0-a85a-de3132b56f95" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DebtInstrumentOptionToDraw_019c376c-db25-7e61-ad9d-fe70720375ad" xlink:href="hcat-20251231.xsd#hcat_DebtInstrumentOptionToDraw"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_hcat_DebtInstrumentOptionToDraw_019c376c-db25-7e61-ad9d-fe70720375ad" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DebtInstrumentDelayedDrawFacilityTerm_019c376c-db25-7e7e-bfbf-6d0681ae72e0" xlink:href="hcat-20251231.xsd#hcat_DebtInstrumentDelayedDrawFacilityTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_hcat_DebtInstrumentDelayedDrawFacilityTerm_019c376c-db25-7e7e-bfbf-6d0681ae72e0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAnnualPrincipalPayment_019c376c-db25-7cd2-8c34-21523dc6faa1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAnnualPrincipalPayment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_DebtInstrumentAnnualPrincipalPayment_019c376c-db25-7cd2-8c34-21523dc6faa1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DebtInstrumentAdditionalDrawAmount_019c376c-db25-76d7-8a80-2e3b8ebbe21c" xlink:href="hcat-20251231.xsd#hcat_DebtInstrumentAdditionalDrawAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_hcat_DebtInstrumentAdditionalDrawAmount_019c376c-db25-76d7-8a80-2e3b8ebbe21c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_019c376c-db25-73b7-a10d-babe139a528c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_019c376c-db25-73b7-a10d-babe139a528c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_019c376c-db25-711d-9adb-8df6133fa076" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_019c376c-db25-711d-9adb-8df6133fa076" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DebtInstrumentQuarterlyPaymentPrincipalPercentage_019c376c-db25-744f-96f1-0b3e19c733e1" xlink:href="hcat-20251231.xsd#hcat_DebtInstrumentQuarterlyPaymentPrincipalPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_hcat_DebtInstrumentQuarterlyPaymentPrincipalPercentage_019c376c-db25-744f-96f1-0b3e19c733e1" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DebtInstrumentPrepaymentPremiumPercentage_019c376c-db25-7a06-9686-8393e4265f3d" xlink:href="hcat-20251231.xsd#hcat_DebtInstrumentPrepaymentPremiumPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_hcat_DebtInstrumentPrepaymentPremiumPercentage_019c376c-db25-7a06-9686-8393e4265f3d" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019c376c-db25-7099-a8bf-b26133d449c3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019c376c-db25-7099-a8bf-b26133d449c3" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfDebt_019c376c-db25-7d56-9ff8-1ac3a7d697b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfDebt_019c376c-db25-7d56-9ff8-1ac3a7d697b5" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeCapPrice_019cd740-ee69-7388-a91e-4581cab2962f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeCapPrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019c376c-db25-7077-98d5-718e9ac52911" xlink:to="loc_us-gaap_DerivativeCapPrice_019cd740-ee69-7388-a91e-4581cab2962f" xlink:type="arc" order="13"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/RestructuringCostsNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#RestructuringCostsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/RestructuringCostsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-796d-b228-5e2166ce2822" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7eb4-b8e8-0d16311c3cdd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-796d-b228-5e2166ce2822" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7eb4-b8e8-0d16311c3cdd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-7298-9775-417e7c6a7db2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7eb4-b8e8-0d16311c3cdd" xlink:to="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-7298-9775-417e7c6a7db2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7298-9775-417e7c6a7db2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-7298-9775-417e7c6a7db2" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7298-9775-417e7c6a7db2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7896-83a9-629b555bd9e5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-7298-9775-417e7c6a7db2" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7896-83a9-629b555bd9e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_August2025RestructuringPlanMember_019c3796-7621-7172-a0f5-af1652eb203b" xlink:href="hcat-20251231.xsd#hcat_August2025RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7896-83a9-629b555bd9e5" xlink:to="loc_hcat_August2025RestructuringPlanMember_019c3796-7621-7172-a0f5-af1652eb203b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringAndRelatedCostExpectedCost1_019b0f49-2e0c-743e-9489-1116cf926a1d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringAndRelatedCostExpectedCost1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-796d-b228-5e2166ce2822" xlink:to="loc_us-gaap_RestructuringAndRelatedCostExpectedCost1_019b0f49-2e0c-743e-9489-1116cf926a1d" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/RestructuringCostsScheduleofRestructuringRelatedChargesandRelatedLiabilityDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#RestructuringCostsScheduleofRestructuringRelatedChargesandRelatedLiabilityDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/RestructuringCostsScheduleofRestructuringRelatedChargesandRelatedLiabilityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-7924-b614-d78283599a34" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7904-83a1-684f9d937d24" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-7924-b614-d78283599a34" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7904-83a1-684f9d937d24" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-70f0-8e6b-77189acc97a8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7904-83a1-684f9d937d24" xlink:to="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-70f0-8e6b-77189acc97a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-70f0-8e6b-77189acc97a8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-70f0-8e6b-77189acc97a8" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-70f0-8e6b-77189acc97a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7d5e-aa93-7a4347743e55" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-70f0-8e6b-77189acc97a8" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7d5e-aa93-7a4347743e55" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_August2025RestructuringPlanMember_019c3779-8ca0-7551-960f-3bd7a01e4347" xlink:href="hcat-20251231.xsd#hcat_August2025RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7d5e-aa93-7a4347743e55" xlink:to="loc_hcat_August2025RestructuringPlanMember_019c3779-8ca0-7551-960f-3bd7a01e4347" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_January2025RestructuringPlanMember_019c3787-a245-7ce1-b23d-cb3cdbed3615" xlink:href="hcat-20251231.xsd#hcat_January2025RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7d5e-aa93-7a4347743e55" xlink:to="loc_hcat_January2025RestructuringPlanMember_019c3787-a245-7ce1-b23d-cb3cdbed3615" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_A2023RestructuringPlanMember_019b10d9-66f1-7cda-820a-7beeff4ffc73" xlink:href="hcat-20251231.xsd#hcat_A2023RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7d5e-aa93-7a4347743e55" xlink:to="loc_hcat_A2023RestructuringPlanMember_019b10d9-66f1-7cda-820a-7beeff4ffc73" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_A2022RestructuringPlanMember_019b0f49-2e0c-7f84-8200-59dbcaa6de4d" xlink:href="hcat-20251231.xsd#hcat_A2022RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7d5e-aa93-7a4347743e55" xlink:to="loc_hcat_A2022RestructuringPlanMember_019b0f49-2e0c-7f84-8200-59dbcaa6de4d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_019b0f49-2e0c-7815-a819-3c453e690246" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCostAndReserveAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7904-83a1-684f9d937d24" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_019b0f49-2e0c-7815-a819-3c453e690246" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019b0f49-2e0c-7815-a819-3c453e690246_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019b0f49-2e0c-7815-a819-3c453e690246" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019b0f49-2e0c-7815-a819-3c453e690246_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019b0f49-2e0c-7c33-a885-83fa49bd1d3a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019b0f49-2e0c-7815-a819-3c453e690246" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019b0f49-2e0c-7c33-a885-83fa49bd1d3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SeveranceAndOtherTeamMemberCostsMember_019b0f49-2e0c-7142-9972-d0047fa9f18b" xlink:href="hcat-20251231.xsd#hcat_SeveranceAndOtherTeamMemberCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_019b0f49-2e0c-7c33-a885-83fa49bd1d3a" xlink:to="loc_hcat_SeveranceAndOtherTeamMemberCostsMember_019b0f49-2e0c-7142-9972-d0047fa9f18b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserveRollForward_019b0f49-2e0c-70a3-a7d3-b84faef43eae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringReserveRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-7924-b614-d78283599a34" xlink:to="loc_us-gaap_RestructuringReserveRollForward_019b0f49-2e0c-70a3-a7d3-b84faef43eae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserve_019b0f49-2e0c-7345-998b-e802e05aa09f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringReserve"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_019b0f49-2e0c-70a3-a7d3-b84faef43eae" xlink:to="loc_us-gaap_RestructuringReserve_019b0f49-2e0c-7345-998b-e802e05aa09f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCosts_019b0f49-2e0c-73c3-a8e5-f64d2fa45341" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_019b0f49-2e0c-70a3-a7d3-b84faef43eae" xlink:to="loc_us-gaap_RestructuringCosts_019b0f49-2e0c-73c3-a8e5-f64d2fa45341" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRestructuring_019b0f49-2e0c-7712-997b-4097e653f1c3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForRestructuring"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_019b0f49-2e0c-70a3-a7d3-b84faef43eae" xlink:to="loc_us-gaap_PaymentsForRestructuring_019b0f49-2e0c-7712-997b-4097e653f1c3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_RestructuringReserveAdjustmentsForNonCashItems_019b0f49-2e0c-787a-bade-155ab441aeab" xlink:href="hcat-20251231.xsd#hcat_RestructuringReserveAdjustmentsForNonCashItems"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_019b0f49-2e0c-70a3-a7d3-b84faef43eae" xlink:to="loc_hcat_RestructuringReserveAdjustmentsForNonCashItems_019b0f49-2e0c-787a-bade-155ab441aeab" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserve_019b0f49-2e0c-7c8b-9a33-918e89640f80" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringReserve"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/RestructuringCostsScheduleofRestructuringCostsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#RestructuringCostsScheduleofRestructuringCostsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/RestructuringCostsScheduleofRestructuringCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-7e64-a552-e79dbd2323a8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7acd-8b98-3adbb8110ae0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-7e64-a552-e79dbd2323a8" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7acd-8b98-3adbb8110ae0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-738a-8862-1e9937a92c20" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7acd-8b98-3adbb8110ae0" xlink:to="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-738a-8862-1e9937a92c20" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-738a-8862-1e9937a92c20_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-738a-8862-1e9937a92c20" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-738a-8862-1e9937a92c20_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7f53-8c9a-0d769a8f18b0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringPlanAxis_019b0f49-2e0c-738a-8862-1e9937a92c20" xlink:to="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7f53-8c9a-0d769a8f18b0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_August2025RestructuringPlanMember_019c3777-4227-7786-9af4-0e38f52ef20e" xlink:href="hcat-20251231.xsd#hcat_August2025RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7f53-8c9a-0d769a8f18b0" xlink:to="loc_hcat_August2025RestructuringPlanMember_019c3777-4227-7786-9af4-0e38f52ef20e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_January2025RestructuringPlanMember_019c378a-05e2-7ccc-8e28-7f9bb154d977" xlink:href="hcat-20251231.xsd#hcat_January2025RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7f53-8c9a-0d769a8f18b0" xlink:to="loc_hcat_January2025RestructuringPlanMember_019c378a-05e2-7ccc-8e28-7f9bb154d977" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_A2023RestructuringPlanMember_019b0f49-2e0c-712e-af36-c2f4d59064f9" xlink:href="hcat-20251231.xsd#hcat_A2023RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7f53-8c9a-0d769a8f18b0" xlink:to="loc_hcat_A2023RestructuringPlanMember_019b0f49-2e0c-712e-af36-c2f4d59064f9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_A2022RestructuringPlanMember_019b0f49-2e0c-721e-be3e-2ff5fd8c3fc4" xlink:href="hcat-20251231.xsd#hcat_A2022RestructuringPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_019b0f49-2e0c-7f53-8c9a-0d769a8f18b0" xlink:to="loc_hcat_A2022RestructuringPlanMember_019b0f49-2e0c-721e-be3e-2ff5fd8c3fc4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0c-745d-865c-fff66dd4206e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7acd-8b98-3adbb8110ae0" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0c-745d-865c-fff66dd4206e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-745d-865c-fff66dd4206e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0c-745d-865c-fff66dd4206e" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-745d-865c-fff66dd4206e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-75c4-94da-ae4433f97446" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0c-745d-865c-fff66dd4206e" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-75c4-94da-ae4433f97446" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyMember_019b0f49-2e0c-7685-9792-2b153dcf9358" xlink:href="hcat-20251231.xsd#hcat_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-75c4-94da-ae4433f97446" xlink:to="loc_hcat_TechnologyMember_019b0f49-2e0c-7685-9792-2b153dcf9358" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ProfessionalServicesMember_019c378a-05e2-72f6-89a1-a5384fbf68b8" xlink:href="hcat-20251231.xsd#hcat_ProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-75c4-94da-ae4433f97446" xlink:to="loc_hcat_ProfessionalServicesMember_019c378a-05e2-72f6-89a1-a5384fbf68b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_019b0f49-2e0c-714f-9047-d7c9d9ce9a21" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-75c4-94da-ae4433f97446" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_019b0f49-2e0c-714f-9047-d7c9d9ce9a21" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember_019b0f49-2e0c-7d12-a160-18daf1252cdd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-75c4-94da-ae4433f97446" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpenseMember_019b0f49-2e0c-7d12-a160-18daf1252cdd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_019b0f49-2e0c-7fd2-b1b4-e964303d333c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0c-75c4-94da-ae4433f97446" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_019b0f49-2e0c-7fd2-b1b4-e964303d333c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_019c7080-e34c-736c-a698-9ace24d03ea8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCostAndReserveAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019b0f49-2e0c-7acd-8b98-3adbb8110ae0" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_019c7080-e34c-736c-a698-9ace24d03ea8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019c7080-e34c-736c-a698-9ace24d03ea8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019c7080-e34c-736c-a698-9ace24d03ea8" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019c7080-e34c-736c-a698-9ace24d03ea8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019c7080-e34c-7959-92de-252b619cfeeb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019c7080-e34c-736c-a698-9ace24d03ea8" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019c7080-e34c-7959-92de-252b619cfeeb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SeveranceAndOtherTeamMemberCostsMember_019c7080-e34c-703b-bfe9-215ade42eace" xlink:href="hcat-20251231.xsd#hcat_SeveranceAndOtherTeamMemberCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_019c7080-e34c-7959-92de-252b619cfeeb" xlink:to="loc_hcat_SeveranceAndOtherTeamMemberCostsMember_019c7080-e34c-703b-bfe9-215ade42eace" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019b0f49-2e0c-7e64-a552-e79dbd2323a8" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeveranceCosts1_019b0f49-2e0c-7459-b435-04392db5f6fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeveranceCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_us-gaap_SeveranceCosts1_019b0f49-2e0c-7459-b435-04392db5f6fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetImpairmentCharges_019b0f49-2e0c-7e15-9121-2c1e7add0a5a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_us-gaap_AssetImpairmentCharges_019b0f49-2e0c-7e15-9121-2c1e7add0a5a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherRestructuringCosts_019cd258-790c-7c36-8ff6-06be390787ac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherRestructuringCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_us-gaap_OtherRestructuringCosts_019cd258-790c-7c36-8ff6-06be390787ac" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostsAndAssetImpairmentCharges_019b0f49-2e0c-710d-9822-ad5fa4830fd2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCostsAndAssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_us-gaap_RestructuringCostsAndAssetImpairmentCharges_019b0f49-2e0c-710d-9822-ad5fa4830fd2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CumulativeSeveranceCosts_019c7080-e34c-762b-b330-1e3359a77ac1" xlink:href="hcat-20251231.xsd#hcat_CumulativeSeveranceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_hcat_CumulativeSeveranceCosts_019c7080-e34c-762b-b330-1e3359a77ac1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CumulativeAssetImpairmentCharges_019c7080-e34c-71ae-b475-2ba6717798fb" xlink:href="hcat-20251231.xsd#hcat_CumulativeAssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_hcat_CumulativeAssetImpairmentCharges_019c7080-e34c-71ae-b475-2ba6717798fb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CumulativeOtherRestructuringCosts_019c7083-6517-71e8-b352-ab457412aa96" xlink:href="hcat-20251231.xsd#hcat_CumulativeOtherRestructuringCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_hcat_CumulativeOtherRestructuringCosts_019c7083-6517-71e8-b352-ab457412aa96" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CumulativeRestructuringCostsAndAssetImpairmentCharges_019c7084-5557-7034-97a2-3072a5f07108" xlink:href="hcat-20251231.xsd#hcat_CumulativeRestructuringCostsAndAssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_019b0f49-2e0c-7c51-912a-5237bd5da0d6" xlink:to="loc_hcat_CumulativeRestructuringCostsAndAssetImpairmentCharges_019c7084-5557-7034-97a2-3072a5f07108" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/StockholdersEquityNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#StockholdersEquityNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/StockholdersEquityNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_019b0f49-2e0c-7ba5-8c64-6f7ca17582e3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_019b0f49-2e0c-7ba5-8c64-6f7ca17582e3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019b0f49-2e0c-7dba-9ab6-76f21d4bc8e1" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019b0f49-2e0c-7ba5-8c64-6f7ca17582e3" xlink:to="loc_srt_CounterpartyNameAxis_019b0f49-2e0c-7dba-9ab6-76f21d4bc8e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019b0f49-2e0c-7dba-9ab6-76f21d4bc8e1_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019b0f49-2e0c-7dba-9ab6-76f21d4bc8e1" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019b0f49-2e0c-7dba-9ab6-76f21d4bc8e1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019b0f49-2e0c-7b40-8ad7-ba468683d7e2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019b0f49-2e0c-7dba-9ab6-76f21d4bc8e1" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019b0f49-2e0c-7b40-8ad7-ba468683d7e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_VitalwareLLCMember_019b0f49-2e0c-7109-a245-aab5ca1bb285" xlink:href="hcat-20251231.xsd#hcat_VitalwareLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019b0f49-2e0c-7b40-8ad7-ba468683d7e2" xlink:to="loc_hcat_VitalwareLLCMember_019b0f49-2e0c-7109-a245-aab5ca1bb285" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-77d4-ad68-532c3576b572" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019b0f49-2e0c-7ba5-8c64-6f7ca17582e3" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-77d4-ad68-532c3576b572" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-77d4-ad68-532c3576b572_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-77d4-ad68-532c3576b572" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-77d4-ad68-532c3576b572_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7573-97f5-789bec87d570" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0c-77d4-ad68-532c3576b572" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7573-97f5-789bec87d570" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_AbleHealthInc.Member_019b0f49-2e0c-7f64-8bdd-d68d66e49efd" xlink:href="hcat-20251231.xsd#hcat_AbleHealthInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0c-7573-97f5-789bec87d570" xlink:to="loc_hcat_AbleHealthInc.Member_019b0f49-2e0c-7f64-8bdd-d68d66e49efd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_019b0f49-2e0c-74f8-8869-9166592432d1" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019b0f49-2e0c-7ba5-8c64-6f7ca17582e3" xlink:to="loc_srt_ShareRepurchaseProgramAxis_019b0f49-2e0c-74f8-8869-9166592432d1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019b0f49-2e0c-74f8-8869-9166592432d1_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019b0f49-2e0c-74f8-8869-9166592432d1" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019b0f49-2e0c-74f8-8869-9166592432d1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019b0f49-2e0c-7c80-9ed8-49e2eb483c91" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019b0f49-2e0c-74f8-8869-9166592432d1" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019b0f49-2e0c-7c80-9ed8-49e2eb483c91" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ShareRepurchasePlanMember_019b0f49-2e0c-75f7-81fd-b768aff8804f" xlink:href="hcat-20251231.xsd#hcat_ShareRepurchasePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019b0f49-2e0c-7c80-9ed8-49e2eb483c91" xlink:to="loc_hcat_ShareRepurchasePlanMember_019b0f49-2e0c-75f7-81fd-b768aff8804f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_019b0f49-2e0c-7a2b-9e89-3727c792c978" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_019b0f49-2e0c-7a2b-9e89-3727c792c978" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesIssued_019b0f49-2e0c-7134-ad6c-bb905749016a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_PreferredStockSharesIssued_019b0f49-2e0c-7134-ad6c-bb905749016a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_019b0f49-2e0c-7c63-ae89-d8e414eae461" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_PreferredStockSharesOutstanding_019b0f49-2e0c-7c63-ae89-d8e414eae461" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_019b0f49-2e0c-721f-b42a-a3dba4ef9a5b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_019b0f49-2e0c-721f-b42a-a3dba4ef9a5b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_019b0f49-2e0c-7fd8-823e-6e3658a104fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_019b0f49-2e0c-7fd8-823e-6e3658a104fa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_019c9ae4-af93-79ae-8f2b-874204265396" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_SharesOutstanding_019c9ae4-af93-79ae-8f2b-874204265396" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesIssued_019c9ae4-eceb-7af6-af1a-b9de1345e778" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_SharesIssued_019c9ae4-eceb-7af6-af1a-b9de1345e778" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019b6e7f-f896-7f20-b013-2f1e88fb62fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019b6e7f-f896-7f20-b013-2f1e88fb62fa" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_019b6e7f-f896-7b38-a553-1dab59ba4571" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_CommonStockSharesIssued_019b6e7f-f896-7b38-a553-1dab59ba4571" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_StockholdersVote_019b0f49-2e0c-7d62-8797-521c0fb27484" xlink:href="hcat-20251231.xsd#hcat_StockholdersVote"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_hcat_StockholdersVote_019b0f49-2e0c-7d62-8797-521c0fb27484" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCash_019b0f49-2e0c-7f9c-b0c8-20b3db5be8ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_DividendsCash_019b0f49-2e0c-7f9c-b0c8-20b3db5be8ec" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019b0f49-2e0c-7b73-a8cf-fec7dfed43c0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019b0f49-2e0c-7b73-a8cf-fec7dfed43c0" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_019c37a5-001c-7c9b-8681-5f68d4b1952a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_019c37a5-001c-7c9b-8681-5f68d4b1952a" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesRetired_019c37a5-e81d-7527-9373-552de5b0f3a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockSharesRetired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_TreasuryStockSharesRetired_019c37a5-e81d-7527-9373-552de5b0f3a7" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockRetiredCostMethodAmount_019c37a6-4a99-741d-94ed-f4c587ed59f3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockRetiredCostMethodAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_TreasuryStockRetiredCostMethodAmount_019c37a6-4a99-741d-94ed-f4c587ed59f3" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019c37a6-a5ad-71b2-b869-280faafe6fdb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019c37a6-a5ad-71b2-b869-280faafe6fdb" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_019c37a7-3944-7355-9106-b5beaacb3893" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_019c37a7-3944-7355-9106-b5beaacb3893" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019b0f49-2e0c-7cd2-8481-0ba0225e7beb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019b0f49-2e0c-7ce5-a769-a722ea2c4c36" xlink:to="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019b0f49-2e0c-7cd2-8481-0ba0225e7beb" xlink:type="arc" order="17"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/StockholdersEquityScheduleofAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#StockholdersEquityScheduleofAccumulatedOtherComprehensiveIncomeLossDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/StockholdersEquityScheduleofAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019c37ae-d8a8-7426-9464-c14874d1c832" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019c37ae-d8a8-727e-acd2-b1a49d010be7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019c37ae-d8a8-7426-9464-c14874d1c832" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019c37ae-d8a8-727e-acd2-b1a49d010be7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019c37ae-d8a8-7b33-8a93-f9cb3338dc8c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019c37ae-d8a8-727e-acd2-b1a49d010be7" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019c37ae-d8a8-7b33-8a93-f9cb3338dc8c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019c37ae-d8a8-7b33-8a93-f9cb3338dc8c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019c37ae-d8a8-7b33-8a93-f9cb3338dc8c" xlink:to="loc_us-gaap_EquityComponentDomain_019c37ae-d8a8-7b33-8a93-f9cb3338dc8c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019c37ae-d8a8-7840-8f53-8da3d32d8e03" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019c37ae-d8a8-7b33-8a93-f9cb3338dc8c" xlink:to="loc_us-gaap_EquityComponentDomain_019c37ae-d8a8-7840-8f53-8da3d32d8e03" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019c37ae-d8a8-7889-ab26-0a868e5f3bd7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019c37ae-d8a8-7840-8f53-8da3d32d8e03" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019c37ae-d8a8-7889-ab26-0a868e5f3bd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019c37ae-d8a8-7b5f-8eb1-0c4485b12eaa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019c37ae-d8a8-7840-8f53-8da3d32d8e03" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019c37ae-d8a8-7b5f-8eb1-0c4485b12eaa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019c37ae-d8a8-7dfa-9fe5-0e9559dbf6e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019c37ae-d8a8-7840-8f53-8da3d32d8e03" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019c37ae-d8a8-7dfa-9fe5-0e9559dbf6e7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019c37ae-d8a8-76ae-8ee6-8a57043c49a8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019c37ae-d8a8-7426-9464-c14874d1c832" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019c37ae-d8a8-76ae-8ee6-8a57043c49a8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019c37ae-d8a8-7f6c-acba-fcd1ddc89995" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019c37ae-d8a8-76ae-8ee6-8a57043c49a8" xlink:to="loc_us-gaap_StockholdersEquity_019c37ae-d8a8-7f6c-acba-fcd1ddc89995" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_019c37ae-d8a8-7400-a06d-f039c862ac97" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019c37ae-d8a8-76ae-8ee6-8a57043c49a8" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_019c37ae-d8a8-7400-a06d-f039c862ac97" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_019c37ae-d8a8-76aa-9c27-b9c975c7fa43" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019c37ae-d8a8-76ae-8ee6-8a57043c49a8" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_019c37ae-d8a8-76aa-9c27-b9c975c7fa43" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019c37ae-d8a8-7888-88de-3b1883c9540e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/NetLossPerShareScheduleofShareTotalswithaPotentiallyDilutiveImpactDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#NetLossPerShareScheduleofShareTotalswithaPotentiallyDilutiveImpactDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/NetLossPerShareScheduleofShareTotalswithaPotentiallyDilutiveImpactDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019b0f49-2e0c-7a76-9cd3-5f8cd63bfe03" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019b0f49-2e0c-7f27-962d-374720f242d7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019b0f49-2e0c-7a76-9cd3-5f8cd63bfe03" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019b0f49-2e0c-7f27-962d-374720f242d7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019b0f49-2e0c-717f-8187-5027281e5ef6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019b0f49-2e0c-7f27-962d-374720f242d7" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019b0f49-2e0c-717f-8187-5027281e5ef6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-717f-8187-5027281e5ef6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019b0f49-2e0c-717f-8187-5027281e5ef6" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-717f-8187-5027281e5ef6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019b0f49-2e0c-717f-8187-5027281e5ef6" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019b0f49-2e0c-77a5-8d6b-57008689a66e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019b0f49-2e0c-77a5-8d6b-57008689a66e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0c-78d7-b2f3-33d67245d30c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0c-78d7-b2f3-33d67245d30c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0c-78f1-a87e-c5234cba3ca2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PhantomShareUnitsPSUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:to="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0c-78f1-a87e-c5234cba3ca2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_019b0f49-2e0c-7e3d-bca0-dd28f04758d8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:to="loc_us-gaap_SeniorNotesMember_019b0f49-2e0c-7e3d-bca0-dd28f04758d8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_019b0f49-2e0c-74b7-b462-a915671fe82b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:to="loc_us-gaap_RestrictedStockMember_019b0f49-2e0c-74b7-b462-a915671fe82b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ContingentConsiderationMember_019c2ecf-ac6b-7c2e-95de-2c54268a4b21" xlink:href="hcat-20251231.xsd#hcat_ContingentConsiderationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019b0f49-2e0c-7076-9ac1-0b5aff2fce0d" xlink:to="loc_hcat_ContingentConsiderationMember_019c2ecf-ac6b-7c2e-95de-2c54268a4b21" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019c37cb-b7b2-7188-9635-71f3cd2d7cf2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019b0f49-2e0c-7f27-962d-374720f242d7" xlink:to="loc_us-gaap_DebtInstrumentAxis_019c37cb-b7b2-7188-9635-71f3cd2d7cf2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019c37cb-b7b2-7188-9635-71f3cd2d7cf2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019c37cb-b7b2-7188-9635-71f3cd2d7cf2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019c37cb-b7b2-7188-9635-71f3cd2d7cf2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019c37cb-b7b2-7e59-b48f-c9357f729827" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019c37cb-b7b2-7188-9635-71f3cd2d7cf2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019c37cb-b7b2-7e59-b48f-c9357f729827" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CappedCallMember_019c37cb-b7b2-7cd4-8eb6-a6d2bbb3acb9" xlink:href="hcat-20251231.xsd#hcat_CappedCallMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019c37cb-b7b2-7e59-b48f-c9357f729827" xlink:to="loc_hcat_CappedCallMember_019c37cb-b7b2-7cd4-8eb6-a6d2bbb3acb9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019c37cb-b7b2-7d41-b37c-4ebaee4b8337" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019b0f49-2e0c-7f27-962d-374720f242d7" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019c37cb-b7b2-7d41-b37c-4ebaee4b8337" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019c37cb-b7b2-7d41-b37c-4ebaee4b8337_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019c37cb-b7b2-7d41-b37c-4ebaee4b8337" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019c37cb-b7b2-7d41-b37c-4ebaee4b8337_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019c37cb-b7b2-769f-9837-dd5a2f3381b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019c37cb-b7b2-7d41-b37c-4ebaee4b8337" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019c37cb-b7b2-769f-9837-dd5a2f3381b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019c37cb-b7b2-7a4e-8522-496e5224b164" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019c37cb-b7b2-769f-9837-dd5a2f3381b3" xlink:to="loc_us-gaap_CashFlowHedgingMember_019c37cb-b7b2-7a4e-8522-496e5224b164" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019c37cb-b7b2-7ef4-9c2e-f42c6c91b4e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019b0f49-2e0c-7f27-962d-374720f242d7" xlink:to="loc_us-gaap_HedgingDesignationAxis_019c37cb-b7b2-7ef4-9c2e-f42c6c91b4e6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019c37cb-b7b2-7ef4-9c2e-f42c6c91b4e6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019c37cb-b7b2-7ef4-9c2e-f42c6c91b4e6" xlink:to="loc_us-gaap_HedgingDesignationDomain_019c37cb-b7b2-7ef4-9c2e-f42c6c91b4e6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019c37cb-b7b2-76d1-99d2-a4f5c3b47c4f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019c37cb-b7b2-7ef4-9c2e-f42c6c91b4e6" xlink:to="loc_us-gaap_HedgingDesignationDomain_019c37cb-b7b2-76d1-99d2-a4f5c3b47c4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019c37cb-b7b2-7062-b40e-5da95bb20422" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019c37cb-b7b2-76d1-99d2-a4f5c3b47c4f" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019c37cb-b7b2-7062-b40e-5da95bb20422" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019c37cc-0b78-7d2d-906c-c64f3b09db68" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019b0f49-2e0c-7f27-962d-374720f242d7" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019c37cc-0b78-7d2d-906c-c64f3b09db68" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019c37cc-0b78-7d2d-906c-c64f3b09db68_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019c37cc-0b78-7d2d-906c-c64f3b09db68" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019c37cc-0b78-7d2d-906c-c64f3b09db68_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019c37cc-0b78-7c70-8229-89721756a18a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019c37cc-0b78-7d2d-906c-c64f3b09db68" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019c37cc-0b78-7c70-8229-89721756a18a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_CappedCallMember_019c37cc-0b78-7216-8f17-d5304510e75b" xlink:href="hcat-20251231.xsd#hcat_CappedCallMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019c37cc-0b78-7c70-8229-89721756a18a" xlink:to="loc_hcat_CappedCallMember_019c37cc-0b78-7216-8f17-d5304510e75b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019b0f49-2e0c-765e-a535-2636ffcc8f81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019b0f49-2e0c-7a76-9cd3-5f8cd63bfe03" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019b0f49-2e0c-765e-a535-2636ffcc8f81" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeCapPrice_019c37cc-0b78-7ba0-82e7-6b0de173cd81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeCapPrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019b0f49-2e0c-7a76-9cd3-5f8cd63bfe03" xlink:to="loc_us-gaap_DerivativeCapPrice_019c37cc-0b78-7ba0-82e7-6b0de173cd81" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/StockBasedCompensationNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#StockBasedCompensationNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/StockBasedCompensationNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019b0f49-2e0d-7c39-a09e-74fb908f9fa6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:to="loc_us-gaap_PlanNameAxis_019b0f49-2e0d-7c39-a09e-74fb908f9fa6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019b0f49-2e0d-7c39-a09e-74fb908f9fa6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019b0f49-2e0d-7c39-a09e-74fb908f9fa6" xlink:to="loc_us-gaap_PlanNameDomain_019b0f49-2e0d-7c39-a09e-74fb908f9fa6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019b0f49-2e0d-7582-93fb-fbe246f4c9c1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019b0f49-2e0d-7c39-a09e-74fb908f9fa6" xlink:to="loc_us-gaap_PlanNameDomain_019b0f49-2e0d-7582-93fb-fbe246f4c9c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_StockIncentivePlan2011Member_019b0f49-2e0d-74df-8db0-c0febd6e20de" xlink:href="hcat-20251231.xsd#hcat_StockIncentivePlan2011Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019b0f49-2e0d-7582-93fb-fbe246f4c9c1" xlink:to="loc_hcat_StockIncentivePlan2011Member_019b0f49-2e0d-74df-8db0-c0febd6e20de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_StockIncentivePlan2019Member_019b0f49-2e0d-7606-987a-604f0532c88a" xlink:href="hcat-20251231.xsd#hcat_StockIncentivePlan2019Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019b0f49-2e0d-7582-93fb-fbe246f4c9c1" xlink:to="loc_hcat_StockIncentivePlan2019Member_019b0f49-2e0d-7606-987a-604f0532c88a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_StockIncentivePlanMember_019b0f49-2e0d-7e19-a8e8-46cc862f467c" xlink:href="hcat-20251231.xsd#hcat_StockIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019b0f49-2e0d-7582-93fb-fbe246f4c9c1" xlink:to="loc_hcat_StockIncentivePlanMember_019b0f49-2e0d-7e19-a8e8-46cc862f467c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-770c-a28a-09119cd64fde" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:to="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-770c-a28a-09119cd64fde" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-770c-a28a-09119cd64fde_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-770c-a28a-09119cd64fde" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-770c-a28a-09119cd64fde_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7f1d-a19b-741d0fefbc4e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-770c-a28a-09119cd64fde" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7f1d-a19b-741d0fefbc4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019b0f49-2e0d-76bf-8e38-be63e51195c4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7f1d-a19b-741d0fefbc4e" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019b0f49-2e0d-76bf-8e38-be63e51195c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0d-7a7a-8b2d-23d05344fcc9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7f1d-a19b-741d0fefbc4e" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0d-7a7a-8b2d-23d05344fcc9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-7eac-9c2f-f2a421b9b1f2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PhantomShareUnitsPSUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7f1d-a19b-741d0fefbc4e" xlink:to="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-7eac-9c2f-f2a421b9b1f2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_019b0f49-2e0d-721d-90df-6e0dda262fbe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7f1d-a19b-741d0fefbc4e" xlink:to="loc_us-gaap_EmployeeStockMember_019b0f49-2e0d-721d-90df-6e0dda262fbe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_019b0f49-2e0d-706f-828c-0fe83e9b6f92" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7f1d-a19b-741d0fefbc4e" xlink:to="loc_us-gaap_RestrictedStockMember_019b0f49-2e0d-706f-828c-0fe83e9b6f92" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b0f49-2e0d-784e-9122-4381567e1adb" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:to="loc_srt_RangeAxis_019b0f49-2e0d-784e-9122-4381567e1adb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0d-784e-9122-4381567e1adb_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b0f49-2e0d-784e-9122-4381567e1adb" xlink:to="loc_srt_RangeMember_019b0f49-2e0d-784e-9122-4381567e1adb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0d-7def-992f-4fb1cab00e90" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b0f49-2e0d-784e-9122-4381567e1adb" xlink:to="loc_srt_RangeMember_019b0f49-2e0d-7def-992f-4fb1cab00e90" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b0f49-2e0d-7c54-b858-8d08586b667f" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0d-7def-992f-4fb1cab00e90" xlink:to="loc_srt_MinimumMember_019b0f49-2e0d-7c54-b858-8d08586b667f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b0f49-2e0d-7936-b400-936925c87361" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0d-7def-992f-4fb1cab00e90" xlink:to="loc_srt_MaximumMember_019b0f49-2e0d-7936-b400-936925c87361" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_WeightedAverageMember_019b0f49-2e0d-73e4-8189-d2d29eb82b52" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_WeightedAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0d-7def-992f-4fb1cab00e90" xlink:to="loc_srt_WeightedAverageMember_019b0f49-2e0d-73e4-8189-d2d29eb82b52" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingAxis_019b0f49-2e0d-7fd4-912d-279dc89f26c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:to="loc_us-gaap_VestingAxis_019b0f49-2e0d-7fd4-912d-279dc89f26c9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_019b0f49-2e0d-7fd4-912d-279dc89f26c9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VestingAxis_019b0f49-2e0d-7fd4-912d-279dc89f26c9" xlink:to="loc_us-gaap_VestingDomain_019b0f49-2e0d-7fd4-912d-279dc89f26c9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_019b0f49-2e0d-7d14-985f-d4e41afa2a19" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VestingAxis_019b0f49-2e0d-7fd4-912d-279dc89f26c9" xlink:to="loc_us-gaap_VestingDomain_019b0f49-2e0d-7d14-985f-d4e41afa2a19" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_019b0f49-2e0d-7675-b42a-fd20665108ac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_019b0f49-2e0d-7d14-985f-d4e41afa2a19" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_019b0f49-2e0d-7675-b42a-fd20665108ac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_019b0f49-2e0d-77e4-a8d8-39b16c2ff3b6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_019b0f49-2e0d-7d14-985f-d4e41afa2a19" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_019b0f49-2e0d-77e4-a8d8-39b16c2ff3b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_019b0f49-2e0d-718a-871b-0f8e991e9e20" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_019b0f49-2e0d-7d14-985f-d4e41afa2a19" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_019b0f49-2e0d-718a-871b-0f8e991e9e20" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0d-71f8-b22d-860b5ea33fbf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0d-71f8-b22d-860b5ea33fbf" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-71f8-b22d-860b5ea33fbf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0d-71f8-b22d-860b5ea33fbf" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-71f8-b22d-860b5ea33fbf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-7976-83ba-968b413d5c12" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019b0f49-2e0d-71f8-b22d-860b5ea33fbf" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-7976-83ba-968b413d5c12" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_UpfrontHealthcareServicesMember_019c37f2-d618-726c-9169-1806d60d0666" xlink:href="hcat-20251231.xsd#hcat_UpfrontHealthcareServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-7976-83ba-968b413d5c12" xlink:to="loc_hcat_UpfrontHealthcareServicesMember_019c37f2-d618-726c-9169-1806d60d0666" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ERSCorporationMember_019b0f49-2e0d-7048-91ab-dd39933207c4" xlink:href="hcat-20251231.xsd#hcat_ERSCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-7976-83ba-968b413d5c12" xlink:to="loc_hcat_ERSCorporationMember_019b0f49-2e0d-7048-91ab-dd39933207c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ARMUSCorporationMember_019b0f49-2e0d-7b55-9896-fbd7b8aae135" xlink:href="hcat-20251231.xsd#hcat_ARMUSCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-7976-83ba-968b413d5c12" xlink:to="loc_hcat_ARMUSCorporationMember_019b0f49-2e0d-7b55-9896-fbd7b8aae135" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_KPINinjaMember_019b0f49-2e0d-7378-a80c-21bcc01d9767" xlink:href="hcat-20251231.xsd#hcat_KPINinjaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019b0f49-2e0d-7976-83ba-968b413d5c12" xlink:to="loc_hcat_KPINinjaMember_019b0f49-2e0d-7378-a80c-21bcc01d9767" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0d-79c9-a3e2-494b9c580994" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0d-79c9-a3e2-494b9c580994" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0d-79c9-a3e2-494b9c580994_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0d-79c9-a3e2-494b9c580994" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0d-79c9-a3e2-494b9c580994_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0d-7a64-88d3-b3898032f1bf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019b0f49-2e0d-79c9-a3e2-494b9c580994" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0d-7a64-88d3-b3898032f1bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_MeasurementInputTotalShareholderReturnMember_019b0f49-2e0d-7b35-bd01-d999e9adbba2" xlink:href="hcat-20251231.xsd#hcat_MeasurementInputTotalShareholderReturnMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0d-7a64-88d3-b3898032f1bf" xlink:to="loc_hcat_MeasurementInputTotalShareholderReturnMember_019b0f49-2e0d-7b35-bd01-d999e9adbba2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputRevenueMultipleMember_019b0f49-2e0d-714a-8a77-d7552b1d462b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputRevenueMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0d-7a64-88d3-b3898032f1bf" xlink:to="loc_us-gaap_MeasurementInputRevenueMultipleMember_019b0f49-2e0d-714a-8a77-d7552b1d462b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputEbitdaMultipleMember_019b0f49-2e0d-7967-ba46-50dfdb52cab8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputEbitdaMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019b0f49-2e0d-7a64-88d3-b3898032f1bf" xlink:to="loc_us-gaap_MeasurementInputEbitdaMultipleMember_019b0f49-2e0d-7967-ba46-50dfdb52cab8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019c3806-d12a-7668-b7f6-d70335639199" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7a69-9ba2-a523dd49ddd8" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019c3806-d12a-7668-b7f6-d70335639199" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019c3806-d12a-7668-b7f6-d70335639199_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019c3806-d12a-7668-b7f6-d70335639199" xlink:to="loc_us-gaap_EquityComponentDomain_019c3806-d12a-7668-b7f6-d70335639199_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019c3806-d12a-7b4d-8719-6d2775b056c2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019c3806-d12a-7668-b7f6-d70335639199" xlink:to="loc_us-gaap_EquityComponentDomain_019c3806-d12a-7b4d-8719-6d2775b056c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019c3806-d12a-7f5c-bec9-e603f0d48172" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019c3806-d12a-7b4d-8719-6d2775b056c2" xlink:to="loc_us-gaap_CommonStockMember_019c3806-d12a-7f5c-bec9-e603f0d48172" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_019b0f49-2e0d-7d4e-af24-9ca12f350ed7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_019b0f49-2e0d-7d4e-af24-9ca12f350ed7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized_019b0f49-2e0d-748c-87de-48dddabcb2ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized_019b0f49-2e0d-748c-87de-48dddabcb2ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SharebasedCompensationArrangementbySharebasedPaymentAwardPercentageIncreaseOfTheNumberOfCommonStockShares_019b0f49-2e0d-79fe-a221-ba32de62dc7c" xlink:href="hcat-20251231.xsd#hcat_SharebasedCompensationArrangementbySharebasedPaymentAwardPercentageIncreaseOfTheNumberOfCommonStockShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_hcat_SharebasedCompensationArrangementbySharebasedPaymentAwardPercentageIncreaseOfTheNumberOfCommonStockShares_019b0f49-2e0d-79fe-a221-ba32de62dc7c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019b0f49-2e0d-72d9-be45-94464ca91a05" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019b0f49-2e0d-72d9-be45-94464ca91a05" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationArrangementWithIndividualAllocatedShareBasedCompensationExpense_019b0f49-2e0d-785f-a618-74e21cc7aa7d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredCompensationArrangementWithIndividualAllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_DeferredCompensationArrangementWithIndividualAllocatedShareBasedCompensationExpense_019b0f49-2e0d-785f-a618-74e21cc7aa7d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_019b0f49-2e0d-735d-9c7d-a4bda06109b9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_019b0f49-2e0d-735d-9c7d-a4bda06109b9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_019b0f49-2e0d-7abf-8760-2cd18fb4989c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_019b0f49-2e0d-7abf-8760-2cd18fb4989c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_019c37e6-0cb7-7920-ba51-46685a8c2c6a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_019c37e6-0cb7-7920-ba51-46685a8c2c6a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019c37e9-947c-776a-b37f-29b68bcb8e94" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019c37e9-947c-776a-b37f-29b68bcb8e94" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_019b0f49-2e0d-7eff-b586-edce84ea527d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_019b0f49-2e0d-7eff-b586-edce84ea527d" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_019b0f49-2e0d-71e5-a51e-7c2cae1b56e0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_019b0f49-2e0d-71e5-a51e-7c2cae1b56e0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_019b0f49-2e0d-7d8f-a2fd-6a4d0637ac23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_019b0f49-2e0d-7d8f-a2fd-6a4d0637ac23" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019b0f49-2e0d-75f4-83ea-bdd417d970d7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019b0f49-2e0d-75f4-83ea-bdd417d970d7" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019b0f49-2e0d-7f76-851f-1a58e50fc9a8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019b0f49-2e0d-7f76-851f-1a58e50fc9a8" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019b0f49-2e0d-7b69-b401-9cb8c8ea28b2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019b0f49-2e0d-7b69-b401-9cb8c8ea28b2" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardMeasurementPeriod_019b0f49-2e0d-77ef-8c1c-061c04fd7a59" xlink:href="hcat-20251231.xsd#hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardMeasurementPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardMeasurementPeriod_019b0f49-2e0d-77ef-8c1c-061c04fd7a59" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_019b0f49-2e0d-7847-addb-a6bbc4d1349d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_019b0f49-2e0d-7847-addb-a6bbc4d1349d" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOtherIncreasesDecreasesInPeriod_019b0f49-2e0d-726a-b7fa-f0892a05c331" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOtherIncreasesDecreasesInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOtherIncreasesDecreasesInPeriod_019b0f49-2e0d-726a-b7fa-f0892a05c331" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod_019b0f49-2e0d-7ea0-977b-b60708c9300d" xlink:href="hcat-20251231.xsd#hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod_019b0f49-2e0d-7ea0-977b-b60708c9300d" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate_019b0f49-2e0d-7c0a-a6b5-b8c231c0dc3c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate_019b0f49-2e0d-7c0a-a6b5-b8c231c0dc3c" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ShareBasedCompensationArrangementBySharebasedPaymentAwardMaximumPurchaseValueDuringOfferingPeriodPerEmployee_019b0f49-2e0d-7f65-8b75-9a42b8fcdd97" xlink:href="hcat-20251231.xsd#hcat_ShareBasedCompensationArrangementBySharebasedPaymentAwardMaximumPurchaseValueDuringOfferingPeriodPerEmployee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_hcat_ShareBasedCompensationArrangementBySharebasedPaymentAwardMaximumPurchaseValueDuringOfferingPeriodPerEmployee_019b0f49-2e0d-7f65-8b75-9a42b8fcdd97" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_SharebasedCompensationArrangementbySharebasedPaymentAwardMaximumPurchasedSharesAllowed_019b0f49-2e0d-7a64-83ef-c4889b9412fe" xlink:href="hcat-20251231.xsd#hcat_SharebasedCompensationArrangementbySharebasedPaymentAwardMaximumPurchasedSharesAllowed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_hcat_SharebasedCompensationArrangementbySharebasedPaymentAwardMaximumPurchasedSharesAllowed_019b0f49-2e0d-7a64-83ef-c4889b9412fe" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_019b0f49-2e0d-7d8a-badc-473c3b676d1d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_019b0f49-2e0d-7d8a-badc-473c3b676d1d" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_019b0f49-2e0d-7641-8795-30e91e84f64e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_019b0f49-2e0d-7641-8795-30e91e84f64e" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased_019b0f49-2e0d-71ea-924b-f4dc8fd6cccc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased_019b0f49-2e0d-71ea-924b-f4dc8fd6cccc" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_BusinessAcquisitionStockBasedCompensationSharesIssuableNumberOfShares_019b0f49-2e0d-7a9f-9f6e-ac3fb67988bd" xlink:href="hcat-20251231.xsd#hcat_BusinessAcquisitionStockBasedCompensationSharesIssuableNumberOfShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_hcat_BusinessAcquisitionStockBasedCompensationSharesIssuableNumberOfShares_019b0f49-2e0d-7a9f-9f6e-ac3fb67988bd" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan_019c3806-d12a-7fcb-8971-a03157c12a99" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan_019c3806-d12a-7fcb-8971-a03157c12a99" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardAcquisitionDateAnniversaryReleaseOfSharesPeriod_019b0f49-2e0d-7ae1-9fc3-432de78a5ac8" xlink:href="hcat-20251231.xsd#hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardAcquisitionDateAnniversaryReleaseOfSharesPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-706d-a59a-032fcd3831ce" xlink:to="loc_hcat_ShareBasedCompensationArrangementByShareBasedPaymentAwardAcquisitionDateAnniversaryReleaseOfSharesPeriod_019b0f49-2e0d-7ae1-9fc3-432de78a5ac8" xlink:type="arc" order="27"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofEffectofStockbasedCompensationExpenseonStatementofOperationsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#StockBasedCompensationScheduleofEffectofStockbasedCompensationExpenseonStatementofOperationsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofEffectofStockbasedCompensationExpenseonStatementofOperationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7023-8fd0-e8252a125316" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7f93-a796-73000c3a8ebe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7023-8fd0-e8252a125316" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7f93-a796-73000c3a8ebe" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ea3-9889-7221b0c3ec61" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7f93-a796-73000c3a8ebe" xlink:to="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ea3-9889-7221b0c3ec61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7ea3-9889-7221b0c3ec61_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ea3-9889-7221b0c3ec61" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7ea3-9889-7221b0c3ec61_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-70f9-8fd7-65dbf6387cb9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ea3-9889-7221b0c3ec61" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-70f9-8fd7-65dbf6387cb9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019b0f49-2e0d-717c-9948-653b9a817ca6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-70f9-8fd7-65dbf6387cb9" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019b0f49-2e0d-717c-9948-653b9a817ca6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0d-7691-a667-c4e4c0943c4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-70f9-8fd7-65dbf6387cb9" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0d-7691-a667-c4e4c0943c4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-75c5-83df-5294d9a12c1f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PhantomShareUnitsPSUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-70f9-8fd7-65dbf6387cb9" xlink:to="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-75c5-83df-5294d9a12c1f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_019b0f49-2e0d-74e5-8794-4a0ddaf7439e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-70f9-8fd7-65dbf6387cb9" xlink:to="loc_us-gaap_EmployeeStockMember_019b0f49-2e0d-74e5-8794-4a0ddaf7439e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_019b0f49-2e0d-7286-b5df-496f681d8c22" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-70f9-8fd7-65dbf6387cb9" xlink:to="loc_us-gaap_RestrictedStockMember_019b0f49-2e0d-7286-b5df-496f681d8c22" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0d-7143-ace0-5c3540c78193" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7f93-a796-73000c3a8ebe" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0d-7143-ace0-5c3540c78193" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7143-ace0-5c3540c78193_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0d-7143-ace0-5c3540c78193" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7143-ace0-5c3540c78193_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7a8c-988f-e06e933e505e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_019b0f49-2e0d-7143-ace0-5c3540c78193" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7a8c-988f-e06e933e505e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfSalesMember_019b0f49-2e0d-7cf8-b6f4-ee75c68ce3dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7a8c-988f-e06e933e505e" xlink:to="loc_us-gaap_CostOfSalesMember_019b0f49-2e0d-7cf8-b6f4-ee75c68ce3dc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_019b0f49-2e0d-7383-88e7-52a825a19d70" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7a8c-988f-e06e933e505e" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_019b0f49-2e0d-7383-88e7-52a825a19d70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember_019b0f49-2e0d-7c49-9799-ddc6deedbfd4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7a8c-988f-e06e933e505e" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpenseMember_019b0f49-2e0d-7c49-9799-ddc6deedbfd4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_019b0f49-2e0d-72b8-85f3-90a148306976" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019b0f49-2e0d-7a8c-988f-e06e933e505e" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_019b0f49-2e0d-72b8-85f3-90a148306976" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019b0f49-2e0d-7df5-99e1-14eaa357427e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7023-8fd0-e8252a125316" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019b0f49-2e0d-7df5-99e1-14eaa357427e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofFairValueMeasurementInputsandValuationTechniquesDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#StockBasedCompensationScheduleofFairValueMeasurementInputsandValuationTechniquesDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofFairValueMeasurementInputsandValuationTechniquesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7df9-9420-5acce4119463" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7ed7-a3cc-3b3d40367c22" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7df9-9420-5acce4119463" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7ed7-a3cc-3b3d40367c22" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ed8-b324-ebaddc61da4e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7ed7-a3cc-3b3d40367c22" xlink:to="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ed8-b324-ebaddc61da4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7ed8-b324-ebaddc61da4e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ed8-b324-ebaddc61da4e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7ed8-b324-ebaddc61da4e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7a63-91e3-404f4bc6881b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-7ed8-b324-ebaddc61da4e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7a63-91e3-404f4bc6881b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-7377-8f98-b2207b9b5371" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PhantomShareUnitsPSUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7a63-91e3-404f4bc6881b" xlink:to="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-7377-8f98-b2207b9b5371" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b0f49-2e0d-7a2b-b5ee-a250d268b0a6" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7ed7-a3cc-3b3d40367c22" xlink:to="loc_srt_RangeAxis_019b0f49-2e0d-7a2b-b5ee-a250d268b0a6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0d-7a2b-b5ee-a250d268b0a6_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b0f49-2e0d-7a2b-b5ee-a250d268b0a6" xlink:to="loc_srt_RangeMember_019b0f49-2e0d-7a2b-b5ee-a250d268b0a6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0d-786f-bfe3-5d529effe665" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b0f49-2e0d-7a2b-b5ee-a250d268b0a6" xlink:to="loc_srt_RangeMember_019b0f49-2e0d-786f-bfe3-5d529effe665" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b0f49-2e0d-775b-b2db-6184eac64011" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0d-786f-bfe3-5d529effe665" xlink:to="loc_srt_MinimumMember_019b0f49-2e0d-775b-b2db-6184eac64011" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b0f49-2e0d-702b-9f27-d5134eb287a2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0d-786f-bfe3-5d529effe665" xlink:to="loc_srt_MaximumMember_019b0f49-2e0d-702b-9f27-d5134eb287a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_019b0f49-2e0d-7fa4-8882-a00b17c9793a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7df9-9420-5acce4119463" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_019b0f49-2e0d-7fa4-8882-a00b17c9793a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019b0f49-2e0d-7719-8f29-d64a6476e3c3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7df9-9420-5acce4119463" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019b0f49-2e0d-7719-8f29-d64a6476e3c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_019b0f49-2e0d-7be2-ad0f-ca70b77a2355" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7df9-9420-5acce4119463" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_019b0f49-2e0d-7be2-ad0f-ca70b77a2355" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_019b0f49-2e0d-75a6-9b8a-8cb39675fdc2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7df9-9420-5acce4119463" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_019b0f49-2e0d-75a6-9b8a-8cb39675fdc2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_019b0f49-2e0d-7f54-a0ae-93163cfdeca5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7df9-9420-5acce4119463" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_019b0f49-2e0d-7f54-a0ae-93163cfdeca5" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofRestrictedStockUnitandPhantomShareUnitsPSUsActivityDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#StockBasedCompensationScheduleofRestrictedStockUnitandPhantomShareUnitsPSUsActivityDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofRestrictedStockUnitandPhantomShareUnitsPSUsActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7c1c-8ac3-5d955e86c87a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-727c-9242-a36947a1c963" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7c1c-8ac3-5d955e86c87a" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-727c-9242-a36947a1c963" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-71f4-a36c-567ce748550c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-727c-9242-a36947a1c963" xlink:to="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-71f4-a36c-567ce748550c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-71f4-a36c-567ce748550c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-71f4-a36c-567ce748550c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-71f4-a36c-567ce748550c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7cf4-a4ac-ba43e849d5d5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-71f4-a36c-567ce748550c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7cf4-a4ac-ba43e849d5d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0d-728d-a8c6-54d5a519f62e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7cf4-a4ac-ba43e849d5d5" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019b0f49-2e0d-728d-a8c6-54d5a519f62e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-7fcb-bef1-d9016d7b47bf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PhantomShareUnitsPSUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-7cf4-a4ac-ba43e849d5d5" xlink:to="loc_us-gaap_PhantomShareUnitsPSUsMember_019b0f49-2e0d-7fcb-bef1-d9016d7b47bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019b0f49-2e0d-7774-99f9-c22d6747833e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7c1c-8ac3-5d955e86c87a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019b0f49-2e0d-7774-99f9-c22d6747833e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019b0f49-2e0d-7b03-9fe3-666388747716" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019b0f49-2e0d-7774-99f9-c22d6747833e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019b0f49-2e0d-7b03-9fe3-666388747716" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019b0f49-2e0d-711d-b646-f0dd620fa507" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019b0f49-2e0d-7774-99f9-c22d6747833e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019b0f49-2e0d-711d-b646-f0dd620fa507" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019b0f49-2e0d-738c-9465-2cc102d64b8f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019b0f49-2e0d-7774-99f9-c22d6747833e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019b0f49-2e0d-738c-9465-2cc102d64b8f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019b0f49-2e0d-7e96-8e7e-4df38064ad3e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019b0f49-2e0d-7774-99f9-c22d6747833e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019b0f49-2e0d-7e96-8e7e-4df38064ad3e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019b0f49-2e0d-7de6-bab9-26b9d87d4dae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_019b0f49-2e0d-79f4-9eef-73250a863506" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7c1c-8ac3-5d955e86c87a" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_019b0f49-2e0d-79f4-9eef-73250a863506" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019b0f49-2e0d-71ca-8851-6a816ed0116b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_019b0f49-2e0d-79f4-9eef-73250a863506" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019b0f49-2e0d-71ca-8851-6a816ed0116b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019b0f49-2e0d-7a12-beba-80602b42433d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_019b0f49-2e0d-79f4-9eef-73250a863506" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019b0f49-2e0d-7a12-beba-80602b42433d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019b0f49-2e0d-76c6-8e2f-a37a4606102a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_019b0f49-2e0d-79f4-9eef-73250a863506" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019b0f49-2e0d-76c6-8e2f-a37a4606102a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019b0f49-2e0d-7df6-95a6-00bb640057a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_019b0f49-2e0d-79f4-9eef-73250a863506" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019b0f49-2e0d-7df6-95a6-00bb640057a3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019b0f49-2e0d-7ef0-882e-082508a00f78" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofthePurchaseRightfortheESPPOptionAssumptionsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#StockBasedCompensationScheduleofthePurchaseRightfortheESPPOptionAssumptionsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/StockBasedCompensationScheduleofthePurchaseRightfortheESPPOptionAssumptionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7069-87c9-174dc5c7656f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7069-87c9-174dc5c7656f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-73ab-ba4b-db11316df9de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7069-87c9-174dc5c7656f" xlink:to="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-73ab-ba4b-db11316df9de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-73ab-ba4b-db11316df9de_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-73ab-ba4b-db11316df9de" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-73ab-ba4b-db11316df9de_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-76d9-8985-b33bae191fd3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019b0f49-2e0d-73ab-ba4b-db11316df9de" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-76d9-8985-b33bae191fd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_019b0f49-2e0d-7fa1-9b37-ded215db84f0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019b0f49-2e0d-76d9-8985-b33bae191fd3" xlink:to="loc_us-gaap_EmployeeStockMember_019b0f49-2e0d-7fa1-9b37-ded215db84f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b0f49-2e0d-7b36-a3a6-d34e79e75415" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019b0f49-2e0d-7069-87c9-174dc5c7656f" xlink:to="loc_srt_RangeAxis_019b0f49-2e0d-7b36-a3a6-d34e79e75415" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0d-7b36-a3a6-d34e79e75415_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b0f49-2e0d-7b36-a3a6-d34e79e75415" xlink:to="loc_srt_RangeMember_019b0f49-2e0d-7b36-a3a6-d34e79e75415_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b0f49-2e0d-74f4-bff9-c6d9ef9e832a" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b0f49-2e0d-7b36-a3a6-d34e79e75415" xlink:to="loc_srt_RangeMember_019b0f49-2e0d-74f4-bff9-c6d9ef9e832a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b0f49-2e0d-7eaf-8bf2-cce3b9ba8c8f" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0d-74f4-bff9-c6d9ef9e832a" xlink:to="loc_srt_MinimumMember_019b0f49-2e0d-7eaf-8bf2-cce3b9ba8c8f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b0f49-2e0d-72fd-9f0e-a4028142bffb" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b0f49-2e0d-74f4-bff9-c6d9ef9e832a" xlink:to="loc_srt_MaximumMember_019b0f49-2e0d-72fd-9f0e-a4028142bffb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_019b0f49-2e0d-769b-a9b6-14acdd85c5af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_019b0f49-2e0d-769b-a9b6-14acdd85c5af" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_019b0f49-2e0d-7997-831c-fcc10ddadabd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_019b0f49-2e0d-7997-831c-fcc10ddadabd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019b0f49-2e0d-7214-b6f3-0dbf0a9372c6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019b0f49-2e0d-7214-b6f3-0dbf0a9372c6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_019b0f49-2e0d-7175-8f4e-cd7b8e8d38db" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_019b0f49-2e0d-7175-8f4e-cd7b8e8d38db" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_019b0f49-2e0d-7d34-b846-83fe8396059c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_019b0f49-2e0d-7d34-b846-83fe8396059c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_019b0f49-2e0d-7b0d-9093-63ead8dc0074" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_019b0f49-2e0d-7b0d-9093-63ead8dc0074" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_019b0f49-2e0d-7660-b170-58838452fd03" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019b0f49-2e0d-7eaa-9faf-4b530df37557" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_019b0f49-2e0d-7660-b170-58838452fd03" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/IncomeTaxesIncomeTaxPaidDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#IncomeTaxesIncomeTaxPaidDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/IncomeTaxesIncomeTaxPaidDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019c3828-3b50-7ea4-94ae-cc3746f12c6f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionTable_019c3828-3b50-799a-ad3d-d12c7ac29502" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidByIndividualJurisdictionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019c3828-3b50-7ea4-94ae-cc3746f12c6f" xlink:to="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionTable_019c3828-3b50-799a-ad3d-d12c7ac29502" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019c3828-3b50-7edf-96a2-9676a174fb3c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionTable_019c3828-3b50-799a-ad3d-d12c7ac29502" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019c3828-3b50-7edf-96a2-9676a174fb3c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019c3828-3b50-7edf-96a2-9676a174fb3c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019c3828-3b50-7edf-96a2-9676a174fb3c" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019c3828-3b50-7edf-96a2-9676a174fb3c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019c3828-3b50-73fc-9c99-701bf3831dea" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019c3828-3b50-7edf-96a2-9676a174fb3c" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019c3828-3b50-73fc-9c99-701bf3831dea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DomesticCountryMember_019c3838-31e8-7d7f-92c0-a90b46bfcf50" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DomesticCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019c3828-3b50-73fc-9c99-701bf3831dea" xlink:to="loc_us-gaap_DomesticCountryMember_019c3838-31e8-7d7f-92c0-a90b46bfcf50" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StateAndLocalJurisdictionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DomesticCountryMember_019c3838-31e8-7d7f-92c0-a90b46bfcf50" xlink:to="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_TN_019c382a-b0da-780a-9c3c-07254fce750d" xlink:href="https://xbrl.sec.gov/stpr/2025/stpr-2025.xsd#stpr_TN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:to="loc_stpr_TN_019c382a-b0da-780a-9c3c-07254fce750d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_TX_019c382b-5f81-7f54-8261-ef2e73491697" xlink:href="https://xbrl.sec.gov/stpr/2025/stpr-2025.xsd#stpr_TX"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:to="loc_stpr_TX_019c382b-5f81-7f54-8261-ef2e73491697" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_LA_019c382b-c46f-70c5-b4d4-4175876929b6" xlink:href="https://xbrl.sec.gov/stpr/2025/stpr-2025.xsd#stpr_LA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:to="loc_stpr_LA_019c382b-c46f-70c5-b4d4-4175876929b6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_MA_019c382c-2ecf-7c98-9e0f-f721670164b9" xlink:href="https://xbrl.sec.gov/stpr/2025/stpr-2025.xsd#stpr_MA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:to="loc_stpr_MA_019c382c-2ecf-7c98-9e0f-f721670164b9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_NY_019c382c-937f-781b-9ff3-1482b760ea2c" xlink:href="https://xbrl.sec.gov/stpr/2025/stpr-2025.xsd#stpr_NY"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:to="loc_stpr_NY_019c382c-937f-781b-9ff3-1482b760ea2c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StateAndLocalTaxJurisdictionOtherMember_019c3838-c320-7ecd-aac7-08aab48cebc1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StateAndLocalTaxJurisdictionOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StateAndLocalJurisdictionMember_019c3830-0ee8-7c0e-ad91-2040ab6b2c18" xlink:to="loc_us-gaap_StateAndLocalTaxJurisdictionOtherMember_019c3838-c320-7ecd-aac7-08aab48cebc1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_019c3828-3b50-7478-b1e0-55cdb17a8e40" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019c3828-3b50-73fc-9c99-701bf3831dea" xlink:to="loc_us-gaap_ForeignCountryMember_019c3828-3b50-7478-b1e0-55cdb17a8e40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_IN_019c3833-18a3-72f4-af2a-de42e26a2cbe" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_IN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019c3828-3b50-7478-b1e0-55cdb17a8e40" xlink:to="loc_country_IN_019c3833-18a3-72f4-af2a-de42e26a2cbe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_019c3828-3b50-7083-aed5-b3ba570e5f49" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019c3828-3b50-7478-b1e0-55cdb17a8e40" xlink:to="loc_country_GB_019c3828-3b50-7083-aed5-b3ba570e5f49" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019c3828-3b50-791d-8c8a-f236af005ecc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignTaxJurisdictionOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019c3828-3b50-7478-b1e0-55cdb17a8e40" xlink:to="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019c3828-3b50-791d-8c8a-f236af005ecc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidFederalAfterRefundReceived_019c3828-3b50-7a65-a2f4-c017c0d7d6e9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidFederalAfterRefundReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019c3828-3b50-7ea4-94ae-cc3746f12c6f" xlink:to="loc_us-gaap_IncomeTaxPaidFederalAfterRefundReceived_019c3828-3b50-7a65-a2f4-c017c0d7d6e9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidStateAndLocalAfterRefundReceived_019c3828-3b50-73b9-b17b-53bf41b3528c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidStateAndLocalAfterRefundReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019c3828-3b50-7ea4-94ae-cc3746f12c6f" xlink:to="loc_us-gaap_IncomeTaxPaidStateAndLocalAfterRefundReceived_019c3828-3b50-73b9-b17b-53bf41b3528c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidForeignAfterRefundReceivedAbstract_019c3828-3b50-7763-b3ee-cbe6d40d2509" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidForeignAfterRefundReceivedAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019c3828-3b50-7ea4-94ae-cc3746f12c6f" xlink:to="loc_us-gaap_IncomeTaxPaidForeignAfterRefundReceivedAbstract_019c3828-3b50-7763-b3ee-cbe6d40d2509" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidForeignAfterRefundReceived_019c3828-3b50-70c6-9569-098ae9490242" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidForeignAfterRefundReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxPaidForeignAfterRefundReceivedAbstract_019c3828-3b50-7763-b3ee-cbe6d40d2509" xlink:to="loc_us-gaap_IncomeTaxPaidForeignAfterRefundReceived_019c3828-3b50-70c6-9569-098ae9490242" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaidNet_019c3828-3b50-7c33-ab52-33ce6d5d689f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxesPaidNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019c3828-3b50-7ea4-94ae-cc3746f12c6f" xlink:to="loc_us-gaap_IncomeTaxesPaidNet_019c3828-3b50-7c33-ab52-33ce6d5d689f" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/IncomeTaxesNarrativeDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#IncomeTaxesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/IncomeTaxesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwardsLineItems_019b0f49-2e0d-752c-b8bd-bff65ea3a1e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLossCarryforwardsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwardsTable_019b0f49-2e0d-764d-936d-f5738a43d12d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLossCarryforwardsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_019b0f49-2e0d-752c-b8bd-bff65ea3a1e8" xlink:to="loc_us-gaap_OperatingLossCarryforwardsTable_019b0f49-2e0d-764d-936d-f5738a43d12d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019b0f49-2e0d-7331-be80-67d738bac556" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_019b0f49-2e0d-764d-936d-f5738a43d12d" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019b0f49-2e0d-7331-be80-67d738bac556" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019b0f49-2e0d-7331-be80-67d738bac556_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019b0f49-2e0d-7331-be80-67d738bac556" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019b0f49-2e0d-7331-be80-67d738bac556_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019b0f49-2e0d-7208-a2ec-eb375c4b05be" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019b0f49-2e0d-7331-be80-67d738bac556" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019b0f49-2e0d-7208-a2ec-eb375c4b05be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DomesticCountryMember_019b0f49-2e0d-7822-b6d7-762918c1fcb3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DomesticCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019b0f49-2e0d-7208-a2ec-eb375c4b05be" xlink:to="loc_us-gaap_DomesticCountryMember_019b0f49-2e0d-7822-b6d7-762918c1fcb3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StateAndLocalJurisdictionMember_019b0f49-2e0d-7a9c-bec4-455be371d2b8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StateAndLocalJurisdictionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019b0f49-2e0d-7208-a2ec-eb375c4b05be" xlink:to="loc_us-gaap_StateAndLocalJurisdictionMember_019b0f49-2e0d-7a9c-bec4-455be371d2b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardAxis_019b0f49-2e0d-7e2b-b35d-0e1fc1cc9993" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TaxCreditCarryforwardAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_019b0f49-2e0d-764d-936d-f5738a43d12d" xlink:to="loc_us-gaap_TaxCreditCarryforwardAxis_019b0f49-2e0d-7e2b-b35d-0e1fc1cc9993" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardNameDomain_019b0f49-2e0d-7e2b-b35d-0e1fc1cc9993_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TaxCreditCarryforwardNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxCreditCarryforwardAxis_019b0f49-2e0d-7e2b-b35d-0e1fc1cc9993" xlink:to="loc_us-gaap_TaxCreditCarryforwardNameDomain_019b0f49-2e0d-7e2b-b35d-0e1fc1cc9993_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardNameDomain_019b0f49-2e0d-768b-a6ca-d16f44ad7b5a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TaxCreditCarryforwardNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxCreditCarryforwardAxis_019b0f49-2e0d-7e2b-b35d-0e1fc1cc9993" xlink:to="loc_us-gaap_TaxCreditCarryforwardNameDomain_019b0f49-2e0d-768b-a6ca-d16f44ad7b5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchMember_019b0f49-2e0d-7335-af73-a78bf70bd366" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardNameDomain_019b0f49-2e0d-768b-a6ca-d16f44ad7b5a" xlink:to="loc_us-gaap_ResearchMember_019b0f49-2e0d-7335-af73-a78bf70bd366" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaid_019c3876-ed19-7790-bf73-f2999499ce77" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxesPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_019b0f49-2e0d-752c-b8bd-bff65ea3a1e8" xlink:to="loc_us-gaap_IncomeTaxesPaid_019c3876-ed19-7790-bf73-f2999499ce77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_019b0f49-2e0d-7fc5-9604-54fd85260bd6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_019b0f49-2e0d-752c-b8bd-bff65ea3a1e8" xlink:to="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_019b0f49-2e0d-7fc5-9604-54fd85260bd6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwards_019b0f49-2e0d-753f-8fed-06883cdf8a84" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLossCarryforwards"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_019b0f49-2e0d-752c-b8bd-bff65ea3a1e8" xlink:to="loc_us-gaap_OperatingLossCarryforwards_019b0f49-2e0d-753f-8fed-06883cdf8a84" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardAmount_019b0f49-2e0d-7a95-bedb-746b24694c83" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TaxCreditCarryforwardAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_019b0f49-2e0d-752c-b8bd-bff65ea3a1e8" xlink:to="loc_us-gaap_TaxCreditCarryforwardAmount_019b0f49-2e0d-7a95-bedb-746b24694c83" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_019c387b-c4ab-78d4-a86c-e02755d95e03" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_019b0f49-2e0d-752c-b8bd-bff65ea3a1e8" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_019c387b-c4ab-78d4-a86c-e02755d95e03" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxRateReconciliationfortheYearEnded2025Details" xlink:type="simple" xlink:href="hcat-20251231.xsd#IncomeTaxesScheduleofEffectiveIncomeTaxRateReconciliationfortheYearEnded2025Details"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxRateReconciliationfortheYearEnded2025Details" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019c3848-f5be-7989-b2dc-0623693d1e52" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019c3848-f5be-73ec-884b-da31c0e10c90" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019c3848-f5be-7989-b2dc-0623693d1e52" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019c3848-f5be-73ec-884b-da31c0e10c90" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019c3848-f5be-74ed-9e56-dffc56046deb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019c3848-f5be-73ec-884b-da31c0e10c90" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019c3848-f5be-74ed-9e56-dffc56046deb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019c3848-f5be-74ed-9e56-dffc56046deb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019c3848-f5be-74ed-9e56-dffc56046deb" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019c3848-f5be-74ed-9e56-dffc56046deb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019c3848-f5be-7a9e-8011-ee25ab82aed3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019c3848-f5be-74ed-9e56-dffc56046deb" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019c3848-f5be-7a9e-8011-ee25ab82aed3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_019c3848-f5be-771c-b520-37c8b0dd1afe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019c3848-f5be-7a9e-8011-ee25ab82aed3" xlink:to="loc_us-gaap_ForeignCountryMember_019c3848-f5be-771c-b520-37c8b0dd1afe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_019c3855-69cd-726d-82f1-6f1bdebf2149" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019c3848-f5be-771c-b520-37c8b0dd1afe" xlink:to="loc_country_GB_019c3855-69cd-726d-82f1-6f1bdebf2149" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019c90c4-04d2-7e67-be10-713555e13e55" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignTaxJurisdictionOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019c3848-f5be-771c-b520-37c8b0dd1afe" xlink:to="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019c90c4-04d2-7e67-be10-713555e13e55" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DomesticCountryMember_019c386f-a84d-7ef0-b164-9b6447f2c2df" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DomesticCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019c3848-f5be-7a9e-8011-ee25ab82aed3" xlink:to="loc_us-gaap_DomesticCountryMember_019c386f-a84d-7ef0-b164-9b6447f2c2df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019c3858-496a-7db2-94fd-3ae7333db183" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DomesticCountryMember_019c386f-a84d-7ef0-b164-9b6447f2c2df" xlink:to="loc_country_US_019c3858-496a-7db2-94fd-3ae7333db183" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019c3848-f5be-7989-b2dc-0623693d1e52" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_019c3848-f5be-71c3-978e-4b3e743dc6bb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_019c3848-f5be-71c3-978e-4b3e743dc6bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_019c3848-f5be-7a23-ac81-84770a5fbc5e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_019c3848-f5be-7a23-ac81-84770a5fbc5e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses_019c3857-09ae-727e-ae45-f094d1fedf98" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses_019c3857-09ae-727e-ae45-f094d1fedf98" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_019c3848-f5be-72cf-97f7-099349e80fca" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_019c3848-f5be-72cf-97f7-099349e80fca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_019c385b-db7f-7485-ae03-e17a2412d4f5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationOtherAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_019c385b-db7f-7485-ae03-e17a2412d4f5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_019c3848-f5be-7e2f-a6ab-78b6c2eeef5f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_019c3848-f5be-7e2f-a6ab-78b6c2eeef5f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_019c3848-f5be-7834-b16b-66449564bfce" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_019c3848-f5be-7834-b16b-66449564bfce" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_019c3848-f5be-73c4-8d0e-d7caee904c59" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_019c3848-f5be-73c4-8d0e-d7caee904c59" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019c3848-f5be-7b24-bdda-fea27c991e6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019c3848-f5be-723c-a480-8cec6d484537" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019c3848-f5be-7b24-bdda-fea27c991e6c" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019c3848-f5be-7989-b2dc-0623693d1e52" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019c3848-f5be-783f-8aed-7c467ae2bb4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019c3848-f5be-783f-8aed-7c467ae2bb4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_019c3848-f5be-7445-b43d-99e78537571c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_019c3848-f5be-7445-b43d-99e78537571c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_019c3857-94fc-7741-b76c-2cb4d033fca5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_019c3857-94fc-7741-b76c-2cb4d033fca5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_019c3848-f5be-733b-8f63-aff6da263bde" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_019c3848-f5be-733b-8f63-aff6da263bde" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_019c385b-db7f-7fb9-9d2e-b2178c911f36" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_019c385b-db7f-7fb9-9d2e-b2178c911f36" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_019c3848-f5be-745a-8678-a568ceab230f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_019c3848-f5be-745a-8678-a568ceab230f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_019c3848-f5be-7672-99e6-5acc38f17166" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_019c3848-f5be-7672-99e6-5acc38f17166" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_019c3848-f5be-70f9-94e9-3b59390dd381" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_019c3848-f5be-70f9-94e9-3b59390dd381" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_019c3848-f5be-72c5-8c3d-d46e925fc609" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019c3848-f5be-72e4-8b2f-bddb9cd5e079" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_019c3848-f5be-72c5-8c3d-d46e925fc609" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/ContingenciesDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#ContingenciesDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/ContingenciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_019b0f49-2e0d-73a7-a713-e8327a8a1b4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_019b0f49-2e0d-770d-a79f-4c4c1b9811f7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_019b0f49-2e0d-73a7-a713-e8327a8a1b4c" xlink:to="loc_us-gaap_LossContingenciesTable_019b0f49-2e0d-770d-a79f-4c4c1b9811f7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusAxis_019b0f49-2e0d-7d7f-b0d5-01f35e258bea" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LitigationStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019b0f49-2e0d-770d-a79f-4c4c1b9811f7" xlink:to="loc_us-gaap_LitigationStatusAxis_019b0f49-2e0d-7d7f-b0d5-01f35e258bea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusDomain_019b0f49-2e0d-7d7f-b0d5-01f35e258bea_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LitigationStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LitigationStatusAxis_019b0f49-2e0d-7d7f-b0d5-01f35e258bea" xlink:to="loc_us-gaap_LitigationStatusDomain_019b0f49-2e0d-7d7f-b0d5-01f35e258bea_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusDomain_019b0f49-2e0d-701f-886a-63b91a29b48e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LitigationStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LitigationStatusAxis_019b0f49-2e0d-7d7f-b0d5-01f35e258bea" xlink:to="loc_us-gaap_LitigationStatusDomain_019b0f49-2e0d-701f-886a-63b91a29b48e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SettledLitigationMember_019b0f49-2e0d-7234-8af2-7e0c4d28fa03" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SettledLitigationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LitigationStatusDomain_019b0f49-2e0d-701f-886a-63b91a29b48e" xlink:to="loc_us-gaap_SettledLitigationMember_019b0f49-2e0d-7234-8af2-7e0c4d28fa03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationSettlementAmountAwardedToOtherParty_019b0f49-2e0d-769f-b86b-94c630408983" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LitigationSettlementAmountAwardedToOtherParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019b0f49-2e0d-73a7-a713-e8327a8a1b4c" xlink:to="loc_us-gaap_LitigationSettlementAmountAwardedToOtherParty_019b0f49-2e0d-769f-b86b-94c630408983" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/ContractBalancesandPerformanceObligationsDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#ContractBalancesandPerformanceObligationsDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/ContractBalancesandPerformanceObligationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfProductInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:to="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7a16-bfb5-60f8392d7e32_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:to="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7a16-bfb5-60f8392d7e32_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7209-af56-66f3cd046797" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:to="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7209-af56-66f3cd046797" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyAndProfessionalServicesMember_019b1088-d6e0-7be4-8f11-887b975d7a5e" xlink:href="hcat-20251231.xsd#hcat_TechnologyAndProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7209-af56-66f3cd046797" xlink:to="loc_hcat_TechnologyAndProfessionalServicesMember_019b1088-d6e0-7be4-8f11-887b975d7a5e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:to="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b1088-d6e0-7603-b07c-9cdfad1b04a1_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:to="loc_srt_RangeMember_019b1088-d6e0-7603-b07c-9cdfad1b04a1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:to="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b1088-d6e0-7bda-927e-fadfc08d03c6" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:to="loc_srt_MinimumMember_019b1088-d6e0-7bda-927e-fadfc08d03c6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b1088-d6e0-7a5f-9035-dcda96bb1629" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:to="loc_srt_MaximumMember_019b1088-d6e0-7a5f-9035-dcda96bb1629" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_019b1088-d6e0-7e4e-a54c-f5857fdf72c2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_019b1088-d6e0-7e4e-a54c-f5857fdf72c2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019b1088-d6e0-7e6f-b81c-928dc9a8f30c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019b1088-d6e0-7e6f-b81c-928dc9a8f30c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiability_019b1088-d6e0-7ef7-a2a4-7716afa2c592" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ContractWithCustomerLiability_019b1088-d6e0-7ef7-a2a4-7716afa2c592" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019b6e7c-d8f4-73c0-90af-fa678273b5dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiabilityRevenueRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019b6e7c-d8f4-73c0-90af-fa678273b5dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ContractWithCustomerLiabilityRevenueRecognizedPercentage_019b1088-d6e0-74ad-8f45-67980dbbf203" xlink:href="hcat-20251231.xsd#hcat_ContractWithCustomerLiabilityRevenueRecognizedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_ContractWithCustomerLiabilityRevenueRecognizedPercentage_019b1088-d6e0-74ad-8f45-67980dbbf203" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractTerm_019b1088-d6e0-7624-8764-fd83b1355ace" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractTerm_019b1088-d6e0-7624-8764-fd83b1355ace" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod_019b1088-d6e0-7eac-b42e-af7fd945f8a5" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod_019b1088-d6e0-7eac-b42e-af7fd945f8a5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractNoticeRequiredForTermination_019b1088-d6e0-76bc-8b18-e71718b09813" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractNoticeRequiredForTermination"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractNoticeRequiredForTermination_019b1088-d6e0-76bc-8b18-e71718b09813" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_019b1088-d6e0-7a87-9acc-6027e24fa681" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_019b1088-d6e0-7a87-9acc-6027e24fa681" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019b1088-d6e0-75f2-b57e-c6b641cd6851" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019b1088-d6e0-75f2-b57e-c6b641cd6851" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019b1088-d6e0-7bd5-8d0a-a98c4cd875e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019b1088-d6e0-7bd5-8d0a-a98c4cd875e1" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/ContractBalancesandPerformanceObligationsDetails_1" xlink:type="simple" xlink:href="hcat-20251231.xsd#ContractBalancesandPerformanceObligationsDetails_1"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/ContractBalancesandPerformanceObligationsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfProductInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:to="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7a16-bfb5-60f8392d7e32_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:to="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7a16-bfb5-60f8392d7e32_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7209-af56-66f3cd046797" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019b1088-d6e0-7a16-bfb5-60f8392d7e32" xlink:to="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7209-af56-66f3cd046797" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyAndProfessionalServicesMember_019b1088-d6e0-7be4-8f11-887b975d7a5e" xlink:href="hcat-20251231.xsd#hcat_TechnologyAndProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019b1088-d6e0-7209-af56-66f3cd046797" xlink:to="loc_hcat_TechnologyAndProfessionalServicesMember_019b1088-d6e0-7be4-8f11-887b975d7a5e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfProductInformationTable_019b1088-d6e0-7617-964c-368ea74d2ab4" xlink:to="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b1088-d6e0-7603-b07c-9cdfad1b04a1_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:to="loc_srt_RangeMember_019b1088-d6e0-7603-b07c-9cdfad1b04a1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019b1088-d6e0-7603-b07c-9cdfad1b04a1" xlink:to="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019b1088-d6e0-7bda-927e-fadfc08d03c6" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:to="loc_srt_MinimumMember_019b1088-d6e0-7bda-927e-fadfc08d03c6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019b1088-d6e0-7a5f-9035-dcda96bb1629" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019b1088-d6e0-7a81-8ed4-babb9f9abaec" xlink:to="loc_srt_MaximumMember_019b1088-d6e0-7a5f-9035-dcda96bb1629" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019b1088-d6e0-7e6f-b81c-928dc9a8f30c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ContractWithCustomerAssetNetCurrent_019b1088-d6e0-7e6f-b81c-928dc9a8f30c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiability_019b1088-d6e0-7ef7-a2a4-7716afa2c592" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ContractWithCustomerLiability_019b1088-d6e0-7ef7-a2a4-7716afa2c592" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019b6e7c-d8f4-73c0-90af-fa678273b5dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiabilityRevenueRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019b6e7c-d8f4-73c0-90af-fa678273b5dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ContractWithCustomerLiabilityRevenueRecognizedPercentage_019b1088-d6e0-74ad-8f45-67980dbbf203" xlink:href="hcat-20251231.xsd#hcat_ContractWithCustomerLiabilityRevenueRecognizedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_ContractWithCustomerLiabilityRevenueRecognizedPercentage_019b1088-d6e0-74ad-8f45-67980dbbf203" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractTerm_019b1088-d6e0-7624-8764-fd83b1355ace" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractTerm_019b1088-d6e0-7624-8764-fd83b1355ace" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod_019b1088-d6e0-7eac-b42e-af7fd945f8a5" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractAllowedTerminationPeriod_019b1088-d6e0-7eac-b42e-af7fd945f8a5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_DeferredRevenueArrangementForServiceContractNoticeRequiredForTermination_019b1088-d6e0-76bc-8b18-e71718b09813" xlink:href="hcat-20251231.xsd#hcat_DeferredRevenueArrangementForServiceContractNoticeRequiredForTermination"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_hcat_DeferredRevenueArrangementForServiceContractNoticeRequiredForTermination_019b1088-d6e0-76bc-8b18-e71718b09813" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_019b1088-d6e0-7a87-9acc-6027e24fa681" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_019b1088-d6e0-7a87-9acc-6027e24fa681" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019b1088-d6e0-75f2-b57e-c6b641cd6851" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019b1088-d6e0-75f2-b57e-c6b641cd6851" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019b1088-d6e0-7bd5-8d0a-a98c4cd875e1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductInformationLineItems_019b1088-d6e0-7756-948a-3aa14d9c26a6" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019b1088-d6e0-7bd5-8d0a-a98c4cd875e1" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/RelatedPartiesDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#RelatedPartiesDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/RelatedPartiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_019b0f49-2e0d-748d-823c-ce8f832dceb5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019b0f49-2e0d-7719-9d97-58260a36a7c7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019b0f49-2e0d-748d-823c-ce8f832dceb5" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019b0f49-2e0d-7719-9d97-58260a36a7c7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019b0f49-2e0d-7d90-8687-54934ec03575" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019b0f49-2e0d-7719-9d97-58260a36a7c7" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019b0f49-2e0d-7d90-8687-54934ec03575" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019b0f49-2e0d-7d90-8687-54934ec03575_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019b0f49-2e0d-7d90-8687-54934ec03575" xlink:to="loc_us-gaap_RelatedPartyDomain_019b0f49-2e0d-7d90-8687-54934ec03575_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019b0f49-2e0d-7bee-aac2-e3e5ba481015" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019b0f49-2e0d-7d90-8687-54934ec03575" xlink:to="loc_us-gaap_RelatedPartyDomain_019b0f49-2e0d-7bee-aac2-e3e5ba481015" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019b0f49-2e0d-7d5c-949a-12c1db90604c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019b0f49-2e0d-7bee-aac2-e3e5ba481015" xlink:to="loc_us-gaap_RelatedPartyMember_019b0f49-2e0d-7d5c-949a-12c1db90604c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019b0f49-2e0d-7dd2-9d25-98e00fb83b18" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAmountsOfTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019b0f49-2e0d-748d-823c-ce8f832dceb5" xlink:to="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019b0f49-2e0d-7dd2-9d25-98e00fb83b18" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019b0f49-2e0d-76b4-8cdb-47b1fb76e618" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019b0f49-2e0d-748d-823c-ce8f832dceb5" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019b0f49-2e0d-76b4-8cdb-47b1fb76e618" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiability_019b0f49-2e0d-785f-9b38-3d1cca559b66" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019b0f49-2e0d-748d-823c-ce8f832dceb5" xlink:to="loc_us-gaap_ContractWithCustomerLiability_019b0f49-2e0d-785f-9b38-3d1cca559b66" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/SegmentsScheduleofSegmentAdjustedGrossProfitDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#SegmentsScheduleofSegmentAdjustedGrossProfitDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/SegmentsScheduleofSegmentAdjustedGrossProfitDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-75a8-ae18-8457dbd3ec39" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingRevenueReconcilingItemLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7699-8427-2053642e3923" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-75a8-ae18-8457dbd3ec39" xlink:to="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7699-8427-2053642e3923" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-736f-a29a-d5dd51634144" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7699-8427-2053642e3923" xlink:to="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-736f-a29a-d5dd51634144" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-736f-a29a-d5dd51634144_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-736f-a29a-d5dd51634144" xlink:to="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-736f-a29a-d5dd51634144_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-7a7f-9a26-96a847652b01" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-736f-a29a-d5dd51634144" xlink:to="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-7a7f-9a26-96a847652b01" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019b0f49-2e0d-79ce-977e-7d0c1607c7b1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-7a7f-9a26-96a847652b01" xlink:to="loc_us-gaap_OperatingSegmentsMember_019b0f49-2e0d-79ce-977e-7d0c1607c7b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaterialReconcilingItemsMember_019b0f49-2e0d-73fc-b076-478a99ba118b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MaterialReconcilingItemsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-7a7f-9a26-96a847652b01" xlink:to="loc_us-gaap_MaterialReconcilingItemsMember_019b0f49-2e0d-73fc-b076-478a99ba118b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-72a8-8bb6-f8a518d6988a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7699-8427-2053642e3923" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-72a8-8bb6-f8a518d6988a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019b0f49-2e0d-72a8-8bb6-f8a518d6988a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-72a8-8bb6-f8a518d6988a" xlink:to="loc_us-gaap_SegmentDomain_019b0f49-2e0d-72a8-8bb6-f8a518d6988a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7581-be01-7a27edd10b71" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-72a8-8bb6-f8a518d6988a" xlink:to="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7581-be01-7a27edd10b71" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyMember_019b0f49-2e0d-7185-ac5c-8ec4da4e6dad" xlink:href="hcat-20251231.xsd#hcat_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7581-be01-7a27edd10b71" xlink:to="loc_hcat_TechnologyMember_019b0f49-2e0d-7185-ac5c-8ec4da4e6dad" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ProfessionalServicesMember_019b0f49-2e0d-7e37-bcfb-194b0a34297b" xlink:href="hcat-20251231.xsd#hcat_ProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7581-be01-7a27edd10b71" xlink:to="loc_hcat_ProfessionalServicesMember_019b0f49-2e0d-7e37-bcfb-194b0a34297b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfitAbstract_019b0f49-2e0d-7338-a254-d31af2ae0e72" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfitAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-75a8-ae18-8457dbd3ec39" xlink:to="loc_us-gaap_GrossProfitAbstract_019b0f49-2e0d-7338-a254-d31af2ae0e72" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019b0f49-2e0d-787d-918e-cba39655a622" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GrossProfitAbstract_019b0f49-2e0d-7338-a254-d31af2ae0e72" xlink:to="loc_us-gaap_GrossProfit_019b0f49-2e0d-787d-918e-cba39655a622" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_LessAdjustedGrossProfitreconcilingitemsAbstract_019b0f49-2e0d-7cec-bee1-d19f96ffda76" xlink:href="hcat-20251231.xsd#hcat_LessAdjustedGrossProfitreconcilingitemsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-75a8-ae18-8457dbd3ec39" xlink:to="loc_hcat_LessAdjustedGrossProfitreconcilingitemsAbstract_019b0f49-2e0d-7cec-bee1-d19f96ffda76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019b0f49-2e0d-7c4b-bf7d-db45f0add442" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessAdjustedGrossProfitreconcilingitemsAbstract_019b0f49-2e0d-7cec-bee1-d19f96ffda76" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019b0f49-2e0d-7c4b-bf7d-db45f0add442" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_019b0f49-2e0d-77cf-9eea-a446b39dbcc5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationAcquisitionRelatedCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessAdjustedGrossProfitreconcilingitemsAbstract_019b0f49-2e0d-7cec-bee1-d19f96ffda76" xlink:to="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_019b0f49-2e0d-77cf-9eea-a446b39dbcc5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCharges_019b0f49-2e0d-7124-b88d-0b0bfd96eedc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessAdjustedGrossProfitreconcilingitemsAbstract_019b0f49-2e0d-7cec-bee1-d19f96ffda76" xlink:to="loc_us-gaap_RestructuringCharges_019b0f49-2e0d-7124-b88d-0b0bfd96eedc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:href="hcat-20251231.xsd#hcat_LessOtherReconcilingItemsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-75a8-ae18-8457dbd3ec39" xlink:to="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpense_019b0f49-2e0d-786c-9b95-2b57c8b25c81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:to="loc_us-gaap_SellingAndMarketingExpense_019b0f49-2e0d-786c-9b95-2b57c8b25c81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_019b0f49-2e0d-7538-a189-83cd2b881b60" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_019b0f49-2e0d-7538-a189-83cd2b881b60" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019b0f49-2e0d-7a9f-ac2d-b1922cedb132" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019b0f49-2e0d-7a9f-ac2d-b1922cedb132" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_019b0f49-2e0d-7a7b-9db1-df75a08daf79" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:to="loc_us-gaap_DepreciationAndAmortization_019b0f49-2e0d-7a7b-9db1-df75a08daf79" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetImpairment_019c3817-f8d7-74fd-b717-05c2abfe03cc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillAndIntangibleAssetImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:to="loc_us-gaap_GoodwillAndIntangibleAssetImpairment_019c3817-f8d7-74fd-b717-05c2abfe03cc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_019b0f49-2e0d-7c07-9d28-d50155ee42cf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_hcat_LessOtherReconcilingItemsAbstract_019b0f49-2e0d-739a-9259-2bda00757a05" xlink:to="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_019b0f49-2e0d-7c07-9d28-d50155ee42cf" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossAttributableToParent_019b0f49-2e0d-76c3-9c95-862694f078bf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-75a8-ae18-8457dbd3ec39" xlink:to="loc_us-gaap_IncomeLossAttributableToParent_019b0f49-2e0d-76c3-9c95-862694f078bf" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.healthcatalyst.com/role/SegmentsScheduledofSegmentRevenueDetails" xlink:type="simple" xlink:href="hcat-20251231.xsd#SegmentsScheduledofSegmentRevenueDetails"/>
  <link:definitionLink xlink:role="http://www.healthcatalyst.com/role/SegmentsScheduledofSegmentRevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-7138-9f2a-de6611105a4d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingRevenueReconcilingItemLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7ffc-a48a-87d8cae4b87d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-7138-9f2a-de6611105a4d" xlink:to="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7ffc-a48a-87d8cae4b87d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-7cf3-9d0d-e26d133abf50" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7ffc-a48a-87d8cae4b87d" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-7cf3-9d0d-e26d133abf50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7cf3-9d0d-e26d133abf50_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-7cf3-9d0d-e26d133abf50" xlink:to="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7cf3-9d0d-e26d133abf50_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7f5b-b51c-90282507fba2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019b0f49-2e0d-7cf3-9d0d-e26d133abf50" xlink:to="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7f5b-b51c-90282507fba2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_TechnologyMember_019b0f49-2e0d-747c-9bfe-52b6c7145f26" xlink:href="hcat-20251231.xsd#hcat_TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7f5b-b51c-90282507fba2" xlink:to="loc_hcat_TechnologyMember_019b0f49-2e0d-747c-9bfe-52b6c7145f26" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_ProfessionalServicesMember_019b0f49-2e0d-726f-a193-5bd6e1ac471b" xlink:href="hcat-20251231.xsd#hcat_ProfessionalServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019b0f49-2e0d-7f5b-b51c-90282507fba2" xlink:to="loc_hcat_ProfessionalServicesMember_019b0f49-2e0d-726f-a193-5bd6e1ac471b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-76df-a51d-ebeff6dd5d6b" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_019b0f49-2e0d-7ffc-a48a-87d8cae4b87d" xlink:to="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-76df-a51d-ebeff6dd5d6b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-76df-a51d-ebeff6dd5d6b_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-76df-a51d-ebeff6dd5d6b" xlink:to="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-76df-a51d-ebeff6dd5d6b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-73f7-bd9d-0cd599de3fd8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019b0f49-2e0d-76df-a51d-ebeff6dd5d6b" xlink:to="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-73f7-bd9d-0cd599de3fd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019b0f49-2e0d-74ab-8346-4ba6ea9b0620" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019b0f49-2e0d-73f7-bd9d-0cd599de3fd8" xlink:to="loc_us-gaap_OperatingSegmentsMember_019b0f49-2e0d-74ab-8346-4ba6ea9b0620" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019b0f49-2e0d-7762-9d68-cd49b4897505" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-7138-9f2a-de6611105a4d" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019b0f49-2e0d-7762-9d68-cd49b4897505" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_hcat_AdjustedCostOfRevenue_019b0f49-2e0d-77d3-a15d-5e1f12f1dc05" xlink:href="hcat-20251231.xsd#hcat_AdjustedCostOfRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-7138-9f2a-de6611105a4d" xlink:to="loc_hcat_AdjustedCostOfRevenue_019b0f49-2e0d-77d3-a15d-5e1f12f1dc05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019b0f49-2e0d-72d1-a3fe-623e6b5a761e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_019b0f49-2e0d-7138-9f2a-de6611105a4d" xlink:to="loc_us-gaap_GrossProfit_019b0f49-2e0d-72d1-a3fe-623e6b5a761e" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd#eedm"/>
  <link:definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetImpairment" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillAndIntangibleAssetImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_GoodwillAndIntangibleAssetImpairment" xlink:type="arc" order="691"/>
  </link:definitionLink>
</link:linkbase>
