|an arrangement in which several males live together with several females, forming a conjugal unit|
the marriage of several men with several women. As an institutionalized social practice, group marriage is extremely rare; nowhere does it appear to have existed as the prevailing form of marital arrangement. Of the 250 societies reported by the American anthropologist George P. Murdock (1949), only the Caingang of Brazil had chosen group marriage as an alternative form of union; even there the frequency was but 8 percent.
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