Polygamy
Polygamy, marriage in which a man has more than one wife at one time (polygyny), or a woman has more than one husband (polyandry). It is still practiced in parts of Asia and Africa; both the Muslim and Hindu religions permit polygyny. It was once also a custom of U.S. Mormons but is now forbidden by them.
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21st Century Webster's Family Encyclopedia21st Century Webster's Family Encyclopedia - Pimento to Popcorn