Meaning ofstool pigeonin English

Noun

1. an informer who betrays associates
   The police used a stool pigeon to gather information about the gang.
2. a cheating device in a gambling game
   A stool pigeon is sometimes used in poker games to cheat other players.
3. a decoy bird tied to a stool; used for hunting
   Hunters would tie a stool pigeon to a stool to lure other birds within shooting range.