'bacchanalia' originates from Latin, specifically the word 'Bacchanalia', where it referred to the festivals of Bacchus (the Roman god of wine).

'bacchanalia' entered English via Latin (Late Latin) from Greek elements such as 'Bakkhai' (Βάκχαι, the Bacchic revelers) and 'Bakkhos' (Βάκχος, the deity); the term passed into English usage retaining its association with Bacchic rites and revelry.

Initially it meant 'religious festivals held in honor of Bacchus'; over time it broadened to mean any riotous, drunken revelry or orgiastic celebration.