MARRIAGE, n. The state or condition of a community consisting of a master, a mistress and two slaves, making in all, two.

Ambrose Bierce (1842-1914?) American writer and journalist

“Marriage,” The Devil’s Dictionary (1911)
    (Source)

Originally published in the "Cynic's Word Book" column in the New York American (1904-08-13), and the "Cynic's Dictionary" column in the San Francisco Examiner (1904-11-15).