Dummy

• dum‧my plural dummies [countable]
• 1

  for clothes

  a model that is the shape and size of a person, especially used in order to show clothes in a shop or when you are making clothes:
• a shop-window dummy
• a tailor's dummy
• 2

  copy

  an object that is made to look like a tool, weapon, vehicle etc but which you cannot use:
• During practice runs, the warheads in the missiles will be dummies.
• 3

  doll

  a small model of a person, with a mouth that can be moved so that it looks as though it is talking, used for entertainment:
• a ventriloquist's dummy
• 4

  sports

  British English a move in a sport such as football in which a player pretends to pass the ball but does not, in order to deceive the other team's players
• 5

  for babies

  British English a specially shaped rubber object that you put in a baby's mouth for it to suck [= pacifier American English]
• 6

  stupid person

  especially American Englishinformal someone who is stupid:
• No, you dummy. The other hand.
• 7

  card game

  cards that are placed on the table by one player for all the other players to see in a game of bridge

• ➔ spit the dummy

   at spit (9)

Definition from the Longman Dictionary of Contemporary English
Advanced Learner's Dictionary.