1561, orgies (pl.) "secret rites in the worship of certain Gk. and Roman gods," especially Dionysus, from M.Fr. orgies (c.1500), from L. orgia, from Gk. orgia (pl.) "secret rites," from PIE base *werg- "to work" (see
urge (v.)). The singular, orgy, was first used in Eng. 1665