A croupier, also called a dealer, runs a table game for the casino. In roulette the croupier spins the wheel, announces the winning number, clears losing bets and pays winners. The word comes from French. The croupier follows fixed rules and has no influence over the result or the odds. Tips are customary in some countries and not in others. In blackjack and poker the role is usually called the dealer instead.
Example
After the ball lands on 17, the croupier places a marker on 17, removes losing chips, then pays the winning bets in order.