wash up, v. — Green’s Dictionary of Slang

wash up v.

[supposedly coined thus: ‘That guy might be all right if he washed up [washed, cleaned himself],’ commented Buck ... Just then the stage manager called out, ‘What will I do with this act, Mr. Ziegfeld?’ ‘Wash up him and the bird,’ said Flo [Ziegfeld] and that was the last of the Italian and his trained canary ... Hype Igoe, the World’s sporting writer, heard of the incident ... and in commenting ... upon Frank Moran, heavy weight pugilist, advised that matchmakers ‘wash him up’. The phrase ... has become a colloquial fixture ... as a meaty synonym for finals and farewell’ (N.Y. World, 25 October 1925); however, note date of wash-up n.]

1. (US) to bring to a conclusion, to end.

1901		Boy’s Own Paper 11 May 498: When we’ve washed up next spring we’ll come and pay a passage home for all you chaps.
1927		B. Cormack Racket Act III: Even gettin’ him to trial won’t wash Nick up.
1930		J. Lait Gangster Girl 163: Why not wash this up tonight?
1941		B. Schulberg What Makes Sammy Run? (1992) 16: I just came down to grab a couple of drinks before washing it [i.e. a piece of writing] up.
1951		M. Spillane One Lonely Night 59: I guess that washes it up then.
1970		San Diego Sailor 74: Let’s wash it up then. What do you want to know about it?

2. to finish a relationship.

1939

W. Winchell On Broadway 9 Sept. [synd. col.] John L. Lewis’ blast at the President the other day washed him up with the White House.

3. (US drugs) to withdraw from narcotics addiction.

1953

Anslinger & Tompkins Traffic In Narcotics 316: wash up. To take the drug cure.

4. to render a failure, to destroy hopes.

1981

E. Bunker Little Boy Blue (1995) 276: He’d be a contender [...] if he’d [...] quit fuckin’ around with that needle. It’s gonna wash him up.

5. to finish a journey.

1998		R.G. Barrett Mud Crab Boogie (2013) [ebook] [T]hey were pommies. Possibly off a ship or just washed up around Bondi with all the rest of the smelly Eurotrash.
2009		T. Black Gutted 243: We washed up back at the Holy Wall. Mac had a pint of Guinness ready.
2023		A. Nette Orphan Road 87: ‘[She] had come to the big smoke and washed up as go-go dancer at the Red Baron’.