heterosexuality n. + Add to list US //ˌhɛtɝoʊsɛkʃəˈwæɫɪti// UK //hˌɛtɹəʊsˈɛkʃuːˈælɪti// het·ero·sex·u·al·i·ty SynonymsEtymology Synonyms straightnessOrigin From heterosexual + -ity or hetero- + sexuality.