1719, variant of kitten, perhaps infl. by kitty "girl, young woman" (c.1500), originally a pet form of Catherine. The sense of "pool of money in a card game" first recorded 1887, probably from kit, in a sense of "collection of necessary supplies" (1833; see kit (1)); but perhaps rather from northern slang kitty "prison, jail, lock-up" (1825), of uncertain origin.