Green’s Dictionary of Slang

1. to hit, to assault.

1931		D. Runyon ‘More Than Somewhat’ in Runyon on Broadway (1954) 161: He is known to boff guys on their noggins.
1944		J. Archibald ‘Skip Tracer Bullets’ in Popular Detective June 🌐 Looks like Huff did have a confederate, maybe, that time he was boffed.
1950		Goldin et al. DAUL 31/1: Boff. 1. To punch; to hit with a blow.
1960, 1975		Wentworth & Flexner DAS.
1974		(con. late 1940s) E. Thompson Tattoo (1977) 581: Hey, honey, we told our ole buddy how good you are, and he would like to boff you too.
1986		C. Hiaasen Tourist Season (1987) 243: A headline that said: Tennis Buff Boffs Bomb Suspect.

2. to copulate with; both heterosexual and homosexual; thus boffing n.

1670		J. Ray Proverbs 52: Offing comes to boffing. Chesh. Offing, i.e. offering or aiming to do.
1938		J. Weidman I Can Get It For You Wholesale 284: Maybe I didn’t get boffed when I went out with Ruthie Rivkin, but I certainly got some swell ideas.
1941–52		in G. Legman Limerick (1953) 259: With bologna you know you’ve been boffed.
1959		‘Andrew Shaw’ Campus Tramp 120: It wasn’t as though Jim Patterson was one of those boys who boff and tell.
1968		G. Vidal Myra Breckenridge 137: Letitia Van Allen who I used to boff in the old days.
1977		(con. 1949) J.G. Dunne True Confessions (1979) 164: Look for rosary beads in the crotch. Crucifixes. Scapulars [...] A definite pattern of Catholic boffing.
1988		H. Gould Double Bang 198: ‘Most wiseguys don’t have relationships with civilians like that, even guys they boffed in the joint.’ [...] ‘And this whole faggot thing,’ Converi said. ‘Most ex-cons don’t talk about that. Wiseguys, never.’.
1999		J. Poller Reach 119: Who would you rather boff – her or me?
2002		J. Ellroy ‘Little Sleazer & the Mail-Sex Mama’ in Destination: Morgue! (2004) 166: Sinatra [...] [t]he frail frame that boffed Ava G.
2010		L. Redhead Thrill City [ebook] How do you know he [...] hasn’t been boffing some Asian chick?
2019		Twitter 19 Feb. 🌐 PMQs so far is like the small talk you make with two mates in the pub when one of them has just boffed the other one's ex-girlfriend and everybody knows but nobody has the bottle to talk about it.
2021		J. Ellroy Widespread Panic 34: He boffed five babes in one week [...] I camera-caught the wives as Jimmy shot them the schvantz.

3. to masturbate.

1984

Partridge DSUE (8th edn) 108/1: since ca. 1930.

4. to lose out, to lose money; to cause someone to lose their money.

1956		J. Cannon Who Struck John? 75: New money moved up to the tables as soon as a player was boffed out [W&F].
1962		S. Longstreet Flesh Peddlers (1964) 198: I drag out a bag (get this) which has five hundred clam shells in it – not money. Never failed to boff ’em.
1979		P. Hamill Deadly Piece 98: Your cousin Ike thought he was boffing Ileana, but probably Monon was boffing Ike.

5. to fail, to blunder, to make a mistake.

1963

M. Spillane Return of the Hood 29: She had passed me something that could make or break our national security and I had boffed it.

6. (US campus) to caress sexually, to ‘neck’.

1967–8

Baker et al. CUSS 84: Boff To neck.