Early 17th century; earliest use found in Philemon Holland (1552–1637), translator. From classical Latin bīga pair of horses (or other animals) or a chariot drawn by them, singular form formed after bīgae (plural), contraction of biiugae (only recorded in grammarians), use as noun (short for biiugae equae mares harnessed four abreast) of feminine plural of biiugus yoked in pairs, (of a chariot) drawn by a pair of horses from bi- + iugum yoke.