copacetic UK /kəʊ.pəˈsɛt.ɪk/US /ˌkoʊ.pəˈsɛt.ɪk/ adjective1 •(US, slang) Fine, excellent, OK, in excellent order.Extract of lemon and ginger ale / Sweet pertuna with shoe polish, then you're bound for jail / "Copacetic" was the password for one and all / The new Jump Steady ball — 1920 formsmore copacetic · most copacetic