Definition of "concubinage" [con•cu•bi•nage]

• Law Cohabitation without legal marriage. (noun)
• The state of being a concubine. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "a courtezan, and the term concubinage to the latter, because a concubine is a substituted partner of the bed, therefore for the sake of distinction, ante-nuptial stipulation with a woman is signified by keeping a mistress, and post-nuptial by concubinage."
• "While she and Constantius were a love match, their only choice was to live together in concubinage, an accepted form of cohabitation for people of different social status."
• ""Fornication of such a gross kind as (exists) not even among the heathen, so that one (of you) hath (in concubinage) his father's wife," that is, his stepmother, while his father is still alive (2Co 7: 12; compare Le 18: 8)."