Webster's Revised Unabridged Dictionary · 1913

Affair

Affair (af*fâr") , noun

[Old English afere, affere, Old French afaire, French affaire, from a faire to do; Latin. ad + facere to do. See Fact, and compare Ado.]

1.
That which is done or is to be done; matter; concern; as, a difficult affair to manage; business of any kind, commercial, professional, or public; -- often in the plural. “At the head of affairs.” Junius.
A talent for affairs. — Prescott
2.
Any proceeding or action which it is wished to refer to or characterize vaguely; as, an affair of honor, i. e., a duel; an affair of love, i. e., an intrigue.
3.
(Military) An action or engagement not of sufficient magnitude to be called a battle.
4.
Action; endeavor. [Obsolete]
And with his best affair Obeyed the pleasure of the Sun. — Chapman
5.
A material object (vaguely designated).
A certain affair of fine red cloth much worn and faded. — Hawthorne