polygynandry
/ˌpɒlɪdʒɪˈnandri/Cultural Anthropol. and Zoology
noun
A form of polygamy in which in two or more men share two or more wives; (Zoology ) a pattern of mating in which two or more males mate with two or more females; the fact or state of being polygynandrous.
Origin
1960s. From polygyn- + -andry. Compare polygynandrous.