Kibitzer is a Yiddish term for a spectator, usually one who offers (often unwanted) advice or commentary. The term can be applied to any activity, but is most commonly used to describe spectators in games such as contract bridge, chess, Go, and Schafkopf.
In card games, a kibitzer simply refers to a spectator watching a player's hand; kibitzers are expected to remain silent and not impact the game.
Kibitz and kibitzer are derived from German kiebitzen, to look over a card-player's shoulder, perhaps derived from Kiebitz, a lapwing or peewit.[1]