Polyandry (; from Greek: πολυ- poly-, “many” and ἀνήρ anēr, “man”) is a form of polygamy in which a woman takes two or more husbands at the same time. Polyandry is contrasted with polygyny, involving one male and two or more females. If a marriage involves a plural number of “husbands and wives” participants of each gender, then it can be called polyamory, group or conjoint marriage. In its broadest use, polyandry refers to sexual relations with multiple males within or without marriage.
Of the 1,231 societies listed in the 1980 Ethnographic Atlas, 186 were found to be monogamous; 453 had occasional polygyny; 588 had more frequent polygyny; and 4 had polyandry. Polyandry is less rare than this figure which listed only those examples found in the Himalayan mountains (28 societies). More recent studies have found more than 50 other societies practising polyandry.