Polygamy

n. practice of maintaining several spouses simultaneously (esp. several wives)

Polygamy has been a feature of human culture since earliest history. The term polygamy (many marriages in late Greek) is used in related ways in social anthropology, sociobiology, and sociology. Polygamy can be defined as any "form of marriage in which a person [has] more than one spouse."In social anthropology, polygamy is the practice of marriage to more than one spouse simultaneously. Historically, polygamy has been practiced as polygyny (one man having more than one wife), or as polyandry (one woman having more than one husband), or, less commonly as "polygamy" (having many wives and many husbands at one time). (See "Forms of Polygamy" below.) In contrast monogamy is the practice of each person having only one spouse. Like monogamy, the term is often used in a de facto sense, applying regardless of whether the relationships are recognized by the state (see marriage for a discussion on the extent to which states can and do recognize potentially and actually polygamous forms as valid).
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Polygamy /po·lyg·a·my/ 1. the concurrent marriage of a woman or man to more than one spouse. 2. animal mating in which the individual mates with [more]Polygamy - Community and Resources

Noun
1. having more than one spouse at a time
(hypernym) marriage, matrimony, union, spousal relationship, wedlock
(hyponym) polyandry

(n.)
The state or habit of having more than one mate.
  

(n.)
The having of a plurality of wives or husbands at the same time; usually, the marriage of a man to more than one woman, or the practice of having several wives, at the same time; -- opposed to monogamy; as, the nations of the East practiced polygamy. See the Note under Bigamy, and cf. Polyandry.
  

(n.)
The condition or state of a plant which bears both perfect and unisexual flowers.