Come - Idioms by The Free Dictionary come 1. verb, vulgar slang To orgasm. The alternate spelling "cum" is often used. I don't think I'll sleep with him again—I didn't come the last time. 2. noun, vulgar slang Semen. Will a black light pick up bodily fluids like come? Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved. come and cum 1. in. to experience an orgasm.