sissy /ˈsɪsi/noun 5adjective 2verb 2forms 5 noun5 •(informal, offensive) An effeminate boy or man. •(slang) A male crossdresser who adopts feminine behaviours. •(informal, offensive) A timid, unassertive or cowardly person.This was all part of football and if any man was such a sissy he could not stand it, then he had better seek the sidelines. — 1963 •(informal, old-fashioned) Sister; often used as a term of address"I so glad - so glad the wicked thing not hurt my sissy!" and in that moment of thankful joy the two children embraced each other with fond affection. — 1862 •(informal) Urination; urine.She has to make. She has to make sissy. — 1997 adjective2 •(offensive) Effeminate.Frontiersmen were never afraid of poetry. It was Big Business with its fear of femininity, it was the eunuchoid clergy capitulating to vulgar masculinity that made religion and art sissy things. — 1976 •(offensive) Cowardly. verb2 •(informal) To urinate.Joan recognized her as the girl whose son had sissied on her pants. She was still dabbing at her pantleg with a damp paper towel. — 1979 •(slang, vulgar) To sissygasm (reach orgasm solely by penetration of the anus). formssissied · sissying · sissies · sissier · sissiest