roulette, game of chance popular in gambling casinos, and in a simplified form elsewhere. In gambling houses the roulette wheel is set in an oblong table. Its outer area is marked off into 37 (in Europe) or 38 (in the United States) spaces, each of which has retaining walls so that a small ball may come to rest in one. The sectors, alternately red and black, are numbered 1 to 36; there is also a green (or sometimes white) 0 and in the United States an additional 00. On the table is an arrangement of red and black squares numbered in correspondence with the wheel. In addition, there are spaces for other types of bets: manque, that the winning number will be 1-18; passe, that it will be 19-36; pair, that it will be an even number; impair, that it will be odd; rouge, that it will be red; noir, that it will be black. All bets are placed against the house and are indicated by placing stakes on the layout. The croupier spins the wheel and tosses the ball onto it; its final place of rest indicates the winning bets. Many betting combinations are allowed, with varying odds and maximum stakes. Roulette dates from the late 18th cent.

Gambling game. After a small ball is released in the opposite direction of a revolving wheel, players make bets concerning which red or black numbered compartment the ball will enter as it comes to rest. Bets are placed on a table marked to correspond with the compartments of the wheel. Roulette (French: “small wheel”) emerged in the late 18th century in the casinos of Europe. All bets are placed against the “house,” or casino bank. Bets may be made until the ball slows down and is about to drop from its track into a compartment. Bets may be on a single number or various combinations of numbers that pay off at lesser odds if the winner is among them. Betting that red or black or that an odd or even number will come up are other options.

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