one-armed bandit

Meanings

1. A gaming machine having a long arm-like handle at one side that a player pulls down to make reels spin; the player wins money or tokens when certain combinations of symbols line up on these reels.
2. Synonym of penny-in-the-slot machine.

Etymology

From one-armed (“having only one arm”) + bandit (“one who robs others in a lawless area, especially as part of a group; one who cheats others”), referring to the fact that the machine is operated by a single handle, and “steals” money from losing players.