ˈjōkə(r) noun
( -s )
1.
a. : a person given to joking : jester , humorist , wag
a joker with an original turn of mind — New Yorker
one of the town jokers put her reluctance to marry down to a hereditary distaste for contracts — Frank O'Connor
b. : guy , bloke , fellow
in walks a joker very skinny and tall — Garson Kanin
what a soft bloody job some jokers have — David Ballantyne
sometimes : an insignificant, obnoxious, or incompetent person : slob
a shame to let a joker like this win — Harold Robbins
know just what to do with that joker — Maxwell Griffith
2.
a. : a small object (as a ball or pea) used in playing thimblerig — called also little joker
b.
(1) : a playing card usually marked on its face with a picture of a jester and often added to a pack of playing cards as a wild card (as in poker or canasta) or as the highest-ranking card (as in five hundred)
(2) : a card designated as wild — see big joker
c.
(1) : a clause that is ambiguous or apparently immaterial inserted in a legislative bill to make it inoperative or uncertain in some respect without arousing opposition at the time of its passage
(2) : an unsuspected, misleading, or misunderstood clause, phrase, or word in an agreement, contract, statement, or other document that in effect nullifies or greatly alters its apparent terms or purport
(3) : something (as an expedient or stratagem) held in reserve to gain one's end or escape from a difficult situation
retained one joker : they could appeal from a Greek legal decision to Roman law — Jaques-Yves Cousteau
(4) : a fact, factor, or condition unsuspected or not apparent at first that thwarts or nullifies an apparent advantage
depreciation: the joker in mechanization — Herrele DeGraff & Ladd Haystead
the joker … is that we have a pretty persistent and devastating way of getting in the way of ourselves — H.A.Overstreet