Real Dictionary

roulette
uncountable noun: Roulette is a gambling game in which a ball is dropped onto a wheel with numbered holes in it while the wheel is spinning round. The players bet on which hole the ball will be in when the wheel stops spinning.

roulette in American English
a gambling game played by rolling a small ball around a shallow bowl with an inner disk (roulette wheel) revolving in the opposite direction: the ball finally comes to rest in one of the red or black, numbered compartments into which this disk is divided,
to make marks, dots, or incisions in or on with a roulette
noun: a game of chance played at a table marked off with numbers from 1 to 36, one or two zeros, and several other sections affording the players a variety of betting opportunities, and having in the center a revolving, dishlike device (roulette wheel) into whi
transitive verb: to mark, impress, or perforate with a roulette

roulette in British English
to use a roulette on (something), as in engraving, making stationery, etc
noun: a gambling game in which a ball is dropped onto a spinning horizontal wheel divided into 37 or 38 coloured and numbered slots, with players betting on the slot into which the ball will fall