a person or thing that stops.

a plug, cork, bung, or other piece for closing a bottle, tube, drain, or the like.

Informal . something or someone that commands attention, as an unusual window display or a flamboyant person.

Cards . a card in a suit that prevents the successive taking of all tricks in the suit by the opponents.

Baseball Slang . a formidably and consistently effective pitcher counted on to win, as a team's best starting pitcher or a superior reliever often called on to preserve a victory; pitching ace.

to close, secure, or fit with a stopper.

noun

choke , cork , fill , stop , bung , lid , plug , stopple , wad