a particular or personal concern
That's my affair, not yours
(in pl) commercial, professional, or public business or matters
world affairs
a procedure, action, or occasion vaguely specified
a social event; a party
informal an object or collection of objects vaguely specified
The house was a ramshackle affair
a temporary amorous or sexual attachment
a matter causing public anxiety, controversy, or scandal
the Dreyfus affair
[Middle English affaire from early French, from a faire to do]