CONCUBINAGE
concubinage (kon-kyoo-b<<schwa>>-nij), n.1. The relationship of a man and woman who cohabit without the benefit of marriage. [Cases: Marriage 22. C.J.S. Marriage §§ 24–25.] 2. The state of being a concubine. 3.Hist. A plea in a dower action made by a defendant who asserts that the plaintiff is the defendant’s concubine rather than wife.
“Concubinage, in common Acceptation is the Keeping of a Whore or Concubine: But in a legal Sense, it is used as an Exception against her that sueth for Dower, alledging thereby that she was not a Wife lawfully married to the Party, in whose Lands she seeks to be endowed, but his Concubine.” Giles Jacob, A New Law-Dictionary (8th ed. 1762). [Blacks Law 8th]