Concubine
Pronunciation : Con"cu*bine
Part of Speech : n.
Etymology : [F., fr. L. concubina; con- + cubare to lie down, concumbere to lie together, akin to E. cubit.]
Definition : 1. A woman who cohabits with a man without being his wife; a paramour.
Note: Concubine has been sometimes, but rarely, used of a male paramour as well as of a female. Trench.
2. A wife of inferior condition; a lawful wife, but not united to the man by the usual ceremonies, and of inferior condition. Such were Hagar and Keturah, the concubines of Abraham; and such concubines were allowed by the Roman laws. Their children were not heirs of their father.
Source : Webster's Unabridged Dictionary, 1913