Synonyms and Antonyms for crotch. crotch (n.) external sex organ. Synonyms: privates. genitals. male genitals. female genitalia. crotch (n.) the angle formed by the inner sides of the legs where they join the human trunk. Synonyms: fork. body. angle. crotch (n.) the region of the angle formed by the junction of two. Synonyms of crotch: groin, lap, crutch | Collins English Thesaurus. Synonyms of crotch - groin. 1'she tipped her dinner over his crotch'. SYNONYMS. groin. lap. Word of the Day. zounds · Find out what it means · Get word of the.