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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e1d79-de4f-7e18-a967-c700b2a82b42,g:b278e5b7-8ddb-4f5e-8047-22988aa69aeb-->
<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.oxy.com/role/Coverpage" xlink:type="simple" xlink:href="oxy-20260710.xsd#Coverpage"/>
  <link:definitionLink xlink:role="http://www.oxy.com/role/Coverpage" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitiesTable_019e1d79-de4f-7bac-9163-e54ff8909d46" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntitiesTable_019e1d79-de4f-7bac-9163-e54ff8909d46" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e1d79-de4f-748e-af95-acd3a174c0df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntitiesTable_019e1d79-de4f-7bac-9163-e54ff8909d46" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e1d79-de4f-748e-af95-acd3a174c0df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e1d79-de4f-748e-af95-acd3a174c0df_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e1d79-de4f-748e-af95-acd3a174c0df" xlink:to="loc_us-gaap_ClassOfStockDomain_019e1d79-de4f-748e-af95-acd3a174c0df_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e1d79-de4f-70e1-937f-0cb1f482cb12" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e1d79-de4f-748e-af95-acd3a174c0df" xlink:to="loc_us-gaap_ClassOfStockDomain_019e1d79-de4f-70e1-937f-0cb1f482cb12" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019e1d79-de4f-7ce3-835c-8d418b1f9859" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e1d79-de4f-70e1-937f-0cb1f482cb12" xlink:to="loc_us-gaap_CommonStockMember_019e1d79-de4f-7ce3-835c-8d418b1f9859" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_oxy_WarrantsToPurchaseCommonStockMember_019e1d79-de4f-78b6-9171-deeb47197174" xlink:href="oxy-20260710.xsd#oxy_WarrantsToPurchaseCommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e1d79-de4f-70e1-937f-0cb1f482cb12" xlink:to="loc_oxy_WarrantsToPurchaseCommonStockMember_019e1d79-de4f-78b6-9171-deeb47197174" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019e1d79-de4f-7ef4-a8ee-52ad559f4ca1" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_DocumentType_019e1d79-de4f-7ef4-a8ee-52ad559f4ca1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019e1d79-de4f-7c68-90a6-9378f8a29ba7" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_DocumentPeriodEndDate_019e1d79-de4f-7c68-90a6-9378f8a29ba7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019e1d79-de4f-7dd9-9f46-7efda5be1108" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityRegistrantName_019e1d79-de4f-7dd9-9f46-7efda5be1108" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019e1d79-de4f-75e1-8f60-07efcb656ce6" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019e1d79-de4f-75e1-8f60-07efcb656ce6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019e1d79-de4f-7c4d-970a-3c92aa07f98c" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityFileNumber_019e1d79-de4f-7c4d-970a-3c92aa07f98c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_019e1d79-de4f-70ff-993f-571389b7c851" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityTaxIdentificationNumber_019e1d79-de4f-70ff-993f-571389b7c851" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019e1d79-de4f-7cd2-86a4-6d35ba25ae21" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityAddressAddressLine1_019e1d79-de4f-7cd2-86a4-6d35ba25ae21" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_019e1d79-de4f-717c-aa34-fcdf3420ac55" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressAddressLine2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityAddressAddressLine2_019e1d79-de4f-717c-aa34-fcdf3420ac55" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019e1d79-de4f-7550-9af4-c46ff36502f1" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityAddressCityOrTown_019e1d79-de4f-7550-9af4-c46ff36502f1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_019e1d79-de4f-70b5-9182-cba50f040b10" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityAddressStateOrProvince_019e1d79-de4f-70b5-9182-cba50f040b10" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019e1d79-de4f-7ec6-8730-4387b1009ad5" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityAddressPostalZipCode_019e1d79-de4f-7ec6-8730-4387b1009ad5" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019e1d79-de4f-7070-9a79-b383b9789d56" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_CityAreaCode_019e1d79-de4f-7070-9a79-b383b9789d56" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019e1d79-de4f-71a7-9382-cba893344406" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_LocalPhoneNumber_019e1d79-de4f-71a7-9382-cba893344406" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_019e1d79-de4f-7fc2-ba1a-b8d5f605a4c9" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_WrittenCommunications"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_WrittenCommunications_019e1d79-de4f-7fc2-ba1a-b8d5f605a4c9" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_019e1d79-de4f-7ab5-a29d-cea8e8a98c4e" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_SolicitingMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_SolicitingMaterial_019e1d79-de4f-7ab5-a29d-cea8e8a98c4e" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_019e1d79-de4f-7ca0-9fb5-9fd7d5e5db63" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_PreCommencementTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_PreCommencementTenderOffer_019e1d79-de4f-7ca0-9fb5-9fd7d5e5db63" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_019e1d79-de4f-71c3-8a50-c5ce71e8e052" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_019e1d79-de4f-71c3-8a50-c5ce71e8e052" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019e1d79-de4f-7c0c-a85d-da0e3e349f4b" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_Security12bTitle_019e1d79-de4f-7c0c-a85d-da0e3e349f4b" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019e1d79-de4f-7bf4-b0b9-d4c95e896e7a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_TradingSymbol_019e1d79-de4f-7bf4-b0b9-d4c95e896e7a" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019e1d79-de4f-7a8f-b89e-d836f0b19ab0" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_SecurityExchangeName_019e1d79-de4f-7a8f-b89e-d836f0b19ab0" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019e1d79-de4f-7b95-97db-9de04caaefaf" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityEmergingGrowthCompany_019e1d79-de4f-7b95-97db-9de04caaefaf" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019e1d79-de4f-79ae-8e16-908fbd7e2268" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_EntityCentralIndexKey_019e1d79-de4f-79ae-8e16-908fbd7e2268" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019e1d79-de4f-73cc-9102-5b7d634fade3" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_019e1d79-de4f-7c72-8756-1f109c6cda87" xlink:to="loc_dei_AmendmentFlag_019e1d79-de4f-73cc-9102-5b7d634fade3" xlink:type="arc" order="22"/>
  </link:definitionLink>
</link:linkbase>
