Green’s Dictionary of Slang

1. crooked dice.

1552		G. Walker Detection of Vyle and Detestable Use of Dice Play in Judges (1926) 35: They call their worthy art by a new-found name calling themselves cheators, and the dice cheaters.
1608		Dekker Belman of London E2: Of all which Lawes, the Highest in place, and the Highest in perdition, is the Cheating Law or the Art of winning money by false dyce: Those that practise this study, call themselves Cheators, the dice Cheaters, and the money which they purchase Cheates.
1931		see sense 2.
1962		see sense 2.

2. (US tramp) marked cards.

1931		Irwin Amer. Tramp and Und. Sl. 49: Cheaters. [...] Marked cards or dishonest dice, no matter how marked or in what way they may be used to cheat. There are many different kinds of ‘cheaters,’ all with some peculiarity giving an advantage to the gambler familiar with their use.
1962		Ragen & Finston World’s Toughest Prison 794: cheaters – Marked cards or dice.