one-armed bandit

or onearm bandit

[ wuhn-ahrmd ]
/ ˈwʌnˌɑrmd /

noun Informal.

Origin of one-armed bandit

An Americanism dating back to 1935–40

British Dictionary definitions for one-armed bandit

one-armed bandit

noun

a fruit machine operated by pulling down a lever at one side

Idioms and Phrases with one-armed bandit

one-armed bandit

A slot machine, as in It's amazing how many people think they can make money playing a one-armed bandit. This term refers to both appearance and function: the operating lever looks like an arm, and the machine in effect robs players, since it “wins” and keeps the player's money in an overwhelming majority of instances. [c. 1930]