GREG - My daughter asked me the definition to a concubine. I didnt know how to define it. This is what i found in one reference,but i dont know if it is correct or not. Does the church have a definition for it that you know of?
con•cu•bine
Pronunciation: (kong'kyu-bîn", kon'-),
—n.
1. a woman who cohabits with a man to whom she is not legally married.
2. (among polygamous peoples) a secondary wife, usually of inferior rank.
3. (esp. formerly in Muslim societies) a woman residing in a harem and kept, as by a sultan, for sexual purposes.

JOEL - The Church doesn't really need its own deffinition of a concubine, any one of the above deffinitions is correct depending on the context. If you are talking about the Bible, a concubine was a woman living in a lawful marriage arrangement with a man, but whose status was regarded as being less than a wife(See deffinition #2).
Concubines were respected, had legal rights, and their children were regarded as legitimate, although the children of the wife (or wives) were most often given preference in matters of inheritance. The inability of a wife to have children was the most common reason for the presence of a concubine in the family.
Anciently some concubines were given to a few of the prophets by the Lord, as in the cases of Abraham and David (D&C 132: 37-39), although some of the concubines David had were not given to him by the Lord, as explained in Jacob in the Book of Mormon(Jacob 2:24).
King Solomon later turned away from God, started worshipping idols, and eventually collected 700 wives and 300 concubines, which were deffinately not given to him by the Lord (1 Kings 11:1-6).