one-armed bandit UK /ˌwʌnɑːmd ˈbændɪt/US /ˌwʌnɑɹmd ˈbændɪt/ noun2 •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. •Synonym of penny-in-the-slot machine. formsone-armed bandits