joker

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. One who tells or plays jokes.
2. n. An insolent person who seeks to make a show of cleverness.
3. n. Informal An annoying or inept person: Some joker is blocking my driveway.
4. n. Games 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.
5. n. A minor clause in a document such as a legislative bill that voids or changes its original or intended purpose.
6. n. An unforeseen but important difficulty, fact, or circumstance.
7. n. A deceptive means of getting the better of someone.

Century Dictionary and Cyclopedia

1. n. One who jokes, in speech or in deed; a jester; a merry fellow.
2. n. 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.
3. n. Figuratively, something concealed that wins the game; a trick under an innocent guise: as, a joker in a legislative bill.

Wiktionary

1. n. A person who makes jokes.
2. n. A funny person
3. n. A jester.
4. n. A playing card that features a picture of a joker (that is, a jester) and that may be used as a wild card in some card games.
5. n. An unspecified, vaguely disreputable person.
6. n. A man.

GNU Webster's 1913

1. n. One who makes jokes or jests.
2. n. See Best bower, under 2d Bower.
3. n. An extra card usually included in a deck of playing cards, having the same design as the others on the back, but on the face having a picture of a jester. It is not included in the deck used in most games, but in certain games may be included and then takes on a special value, such as the highest-valued card, or a wild card.
4. n. A clause placed in a document, such as a contract or a piece of legislation, not itself appearing significant, but in a subtle way substantially changing the effect of the document.
5. n. Any fact or condition which is unknown or not apparent, which reverses an apparently advantageous position; a kicker.
6. n. A person; a fellow; a chap; -- usually used in a mildly disparaging sense.

WordNet 3.0

1. n. an inconspicuous clause in a document or bill that affects its meaning in a way that is not immediately apparent
2. n. a person who enjoys telling or playing jokes
3. n. a playing card that is usually printed with a picture of a jester
4. n. a person who does something thoughtless or annoying