joker

One who tells or plays jokes.

An insolent person who seeks to make a show of cleverness.

An annoying or inept person.

A playing card, usually printed with a picture of a jester, used in certain games as the highest-ranking card or as a wild card.

A clause that is included in a legislative bill or a contract in order to render the bill or contract inoperative or oppressive in some respect while appearing to be innocuous until the harm has been done.

An unforeseen but important difficulty, fact, or circumstance.

A deceptive means of getting the better of someone.

One who jokes, in speech or in deed; a jester; a merry fellow.

A playing-card, either blank or having some comical or other special device, added to a pack, and used in some games, as in euchre. It is always a trump, and generally the highest trump. Often called jolly joker.