Joker

A joker is the common name for the representation of a medieval court jester or harlequin. A joker typically wears a floppy, multi-pointed hat made of cloth fabric with jingle bells at the tips of the points. The joker wears colorful clothing, laughs incessantly, and often holds a mock scepter in his hand.

The term joker is most often a reference to one of two special cards in a Anglo-American playing card deck that are used as wild cards. See Joker (playing card)