Mid 18th century; earliest use found in John Hill (bap. 1714, d. 1775), physician and actor. Originally from scientific Latin Polygynia, order name (Linnaeus Hortus Uplandicus), denoting an order of plants having many pistils (from poly- + ancient Greek γυνή woman, wife, taken by Linnaeus in sense ‘female organ, pistil’ + scientific Latin -ia. Compare Monogynia.