thimblerig

Meanings

1. A game of skill which requires the bettor to guess under which of three small cups (or thimbles) a pea-sized object has been placed after the party operating the game rapidly rearranges them, providing opportunity for sleight-of-hand trickery; a shell game.
2. One operating such a game.

1. To operate a thimblerig game.
2. To cheat (someone) by trickery.

Etymology

From thimble + rig.