stopper

Noun

• blockage consisting of an object designed to fill a hole tightly

• (bridge) a playing card with a value sufficiently high to insure taking a trick in a particular suit
  • if my partner has a spade stopper I can bid no trump
    

• a remark to which there is no polite conversational reply

• an act so striking or impressive that the show must be delayed until the audience quiets down

Verb

• close or secure with or as if with a stopper
  • She stoppered the wine bottle
    
  • The mothers stoppered their babies' mouths with pacifiers
    

Related words

• Synonyms: 
  plug , stopple , conversation stopper , show-stopper , showstopper