Polyandry

(n.) The possession by a woman of more than one husband at the same time; -- contrasted with monandry.

Thesaurus Entries

beena marriage, bigamy, common-law marriage, companionate marriage, concubinage, deuterogamy, left-handed marriage, levirate, leviration, love match, marriage of convenience, monandry, monogamy, monogyny, morganatic marriage, picture marriage, polygamy, polygyny, trial marriage, trigamy