A material object (vaguely designated).
An action or engagement not of sufficient magnitude to be called a battle.
An adulterous relationship (from affaire de cœur, affair of the heart).
A person with whom someone has an adulterous relationship.
A romantic relationship with someone who is not one's regular partner (boyfriend, girlfriend).
Something which is done or is to be done; business of any kind, commercial, professional, or public.
A party or social gathering, especially of a formal nature.
Any proceeding or action which it is wished to refer to or characterize vaguely.
A product or manufactured article, especially an item of art or craft.
A person who has a strong and unusual personality, especially one with seriously unpleasant character flaws (e.g. a nasty piece of work). (This sense came about due to Hamlet’s soliloquy (see sense 1 above)).