Green’s Dictionary of Slang

1. to hit when the victim is not looking or is otherwise unprepared.

1960		C. Cooper Jr Scene (1996) 38: He was getting set to sucker-punch her.
1968		K. Brasselle Cannibals 356: He sucker-punched the guy in the restaurant.
1986		C. Hiaasen Tourist Season (1987) 50: He didn’t feel much like defending any creep who’d sucker-punch him in a place like Pauly’s.
1997		Simon & Burns Corner (1998) 323: To cut him down [...] for $100 or $150 in lost product made about as much sense as sucker-punching that A-rabber’s horse for pissing.
2000		P. Beatty Tuff 58: Sucker-punching the suspect in a chintzy display of cop solidarity.
2004		L. Redhead Peepshow [ebook] Mick sucker punched him in the mouth.
2012		M. McBride Frank Sinatra in a Blender [ebook] Guess he didn’t like being sucker-punched.
2020		(con. 1991-94) W. Boyle City of Margins 51: [S]ucker-punching Captain Dunbar [...] and getting shit-canned so majestically.

2. in fig. use, to shock; thus sucker-punched adj.

2000		J. Ellroy ‘I’ve Got the Goods’ in Destination: Morgue! (2004) 170: Joe and Jane America lived through the Big War and got sucker-punched by Korea.
2001		(con. 1964–8) J. Ellroy Cold Six Thousand 4: People walked past him. They looked sucker-punched.
2023		F. Bill Back to the Dirt 92: ‘I’m fine. My nerves have just been sucker punched is all’.

3. to fool, to trick; thus sucker-punching adj.

1992

R. Price Clockers 397: I’m a man [...] and you all faggots, sucker-punching blind-side faggots that got to keep a man behind bars because you can’t deal with that.