stool pigeon

Etymology
From the act of tying or even nailing a pigeon to a stool to act as a decoy by hunters. Alternatively, from an alteration of 🇰🇲.

Noun

 * 1)  A pigeon tied to a stool by a piece of twine, used as a decoy to entice free-flying birds to the ground to be shot or trapped.
 * 2)  A decoy used in a crooked gambling game.
 * 3)  An informer to the authorities, especially one who gives up criminal associates.

Translations

 * Bulgarian:, мамец
 * Chinese:
 * Mandarin:
 * Esperanto:
 * Finnish:
 * French:, ,
 * German: ,
 * Greek: ,
 * Italian:
 * Norwegian:
 * Bokmål: politispion,
 * Polish: ,
 * Romanian:
 * Russian: ,
 * Spanish:
 * Thai: