rub one out
verbEtymology From the notion of rubbing out seminal ejaculate of one’s penis.
- Irish sounded serious when he said, “Oh, yeah, dog, if you get caught rubbing one out in the joint, you're fucked.” I said, “What's rubbing one out mean?” He cackled, and said, “Whackin' off, chokin' your chicken, spankin' the monkey. Come on dog, don't play stupid.”2012, David Wambaugh, The Last Call, page 178: