- to strike (someone) with an unexpected blow.
- a sudden surprise punch, esp from behind
- a sudden unexpected defeat or setback
Idioms and Phrases with sucker punch
An unexpected blow, as in They felt that suddenly raising the interest rate was a sucker punch to the administration. This expression comes from boxing, where it is used for a punch delivered unexpectedly; boxing great Jack Dempsey wrote, “The right lead [for a right-handed boxer] is called a sucker punch.” [Slang; mid-1900s]