affair

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Something done or to be done; business.
2. n. Transactions and other matters of professional or public business: affairs of state.
3. n. An occurrence, event, or matter: The senator's death was a tragic affair.
4. n. A social function.
5. n. An object or a contrivance: Their first car was a ramshackle affair.
6. n. A matter of personal concern.
7. n. Personal business: get one's affairs in order.
8. n. A matter causing public scandal and controversy: the Dreyfus affair.
9. n. A romantic and sexual relationship, sometimes one of brief duration, between two people who are not married to each other.

Century Dictionary and Cyclopedia

1. n. Anything done or to be done; that which requires action or effort; a moving interest; business; concern: as, this is an affair of great moment; a man of affairs; affairs of state.
2. n. plural Matters of interest or concern; particular doings or interests; specifically, pecuniary interests or relations: as, to meddle with a neighbor's affairs; his affairs are in an embarrassed state.
3. n. An event or a performance; a particular action, operation, or proceeding; military, a partial or minor engagement or contest; a skirmish: as, when did this affair happen: an affair of honor, or of outposts.
4. n. A private or personal concern; a special function, business, or duty.
5. n. Thing; matter; concern: applied to anything made or existing, with a descriptive or qualifying term: as, this machine is a complicated affair; his anger is an affair of no consequence.
6. n. Endeavor; attempt.

Wiktionary

1. n. That which is done or is to be done; matter; concern; business of any kind, commercial, professional, or public; — often in the plural.
2. n. Any proceeding or action which it is wished to refer to or characterize vaguely.
3. n. military An action or engagement not of sufficient magnitude to be called a battle.
4. n. A material object (vaguely designated).
5. n. An adulterous relationship. (from affaire de cœur.)

GNU Webster's 1913

1. n. That which is done or is to be done; matter; concern.
2. n. Any proceeding or action which it is wished to refer to or characterize vaguely.
3. n. (Mil.) An action or engagement not of sufficient magnitude to be called a battle.
4. n. obsolete Action; endeavor.
5. n. A material object (vaguely designated).

WordNet 3.0

1. n. a usually secretive or illicit sexual relationship
2. n. a vaguely specified concern
3. n. a vaguely specified social event