Green’s Dictionary of Slang

1. (US Und.) to beat with a blackjack; thus jacking n.

1929		C. Coe Hooch! 153: Shot, stabbed, or jacked?
1931		G. Milburn ‘Convicts’ Jargon’ in AS VI:6 439: jackin’, n. A beating with a blackjack by the police.
1943		R. Llewellyn None But the Lonely Heart 338: It made you feel you wanted to jack a few more windows, and hear the bash of glass.
1950		Goldin et al. DAUL 109/1: Jack, v. To beat with a blackjack.
1979		E. Torres After Hours 114: A guy that’s been shanked, shot, jacked, brass-knuckled.

2. to masturbate or make a masturbatory gesture (see cit. 2006).

a.1940		‘Peter Pullin’ Blues’ in G. Logsdon Whorehouse Bells Were Ringing (1995) 273: So she skinned my peter back, and that bitch began to jack, / She said, ‘Honey, you have got a pretty rod; / Let me get it hard again, then sweetheart, I’ll put it in, / It will feel good when you’re shootin’ off your wad.’.
1970		in P.R. Runkel Law Unto Themselves 134: Then he says we should jack each other at the same time.
1985		Eble Campus Sl. Apr. 5: jack – to masturbate.
2006		G. Pelecanos Night Gardener 33: Bo green was still lazily jacking his fist.

3. (US prison) to serve a prison sentence.

1966

B. Jackson Get Your Ass in the Water (1974) 52: Gee, judge, that’s no time, I got a brother on Levenworth jackin’ ninety-nine.

4. to break open.

1955

Hal Ellson ‘I Didn’t See a Thing’ in Tell Them Nothing (1956) 135: Poker hit the coop with his crowbar and jacked the lock off.

5. (US prison, also jack up) to stun a fellow inmate with a blackjack before raping.

1972

B. Rodgers Queens’ Vernacular 117: jack somebody up (prison sl) to stun a boy with a weapon before raping him.

6. to stab or punch; usu. as jacked adj.¹ (4)

1997–2001		Online Sl. Dict. 🌐 jack [...] v 1. to stab. 2. to punch. (‘He got jacked in the face.’).
2010		L. Berney Gutshot Straight [ebook] ‘You get lucky and jack Mad Ty, you go straight to the hole’.

7. (UK black) to knock.

2007

D.S. Mitchell Killer Tune (2008) 33: The one and only Notting Hill Carnival [...] is almost jacking at our door.