English

Alternative forms

• sucker-punch

Noun

sucker punch ‎(plural sucker punches)

1. (idiomatic) An unexpected punch or similar blow.
   • 1919 December 9, Jaffe, Louis H., “Murphy Put Away by Blow on Break”, in Evening Public Ledger, volume Vol. VI - No. 74, Philadelphia, Pa., archived from the original on 2016-11-06, page 19:

     Benjamin crossed his right, a short punch traveling less than six inches, as he and Murphy stepped back from the breakaway. Many of the spectators did not see the blow that laid the West Philadelphian low. It was a "sucker punch," as Nick Hayes would have it. Coming out of a clinch, Benjamin took one step backward, then stepped forward before Murphy lifted his arms, crossing his right simultaneously, and zowie-- it was curtains for one of the millions of heroes of the "Big Fight." Jimmy dropped back on his haunches. His eves appeared to be clear, and he knew what he wanted to do--but apparently couldn't do it.

   • 2011 January 8, Chris Bevan, “Arsenal 1 - 1 Leeds”, in BBC:

     The Championship highflyers almost got their reward for a resilient performance on their first visit to the Emirates, surviving a flurry of first-half Arsenal chances before hitting back with a classic sucker punch.

2. (idiomatic) A disabling punch targeting a place which is not normally acceptable in a "fair fight", such as on the back of the head.

Synonyms

• (punch in a place that is not a target in a fair fight): rabbit punch

Verb

sucker punch

1. (idiomatic) To deliver an unexpected blow.