termagant.

PIE word *tréyes The noun is derived from Termagant (“fictitious deity with a violent temperament represented as being worshipped by Muslims or other non-Christians”), from Middle English Termagaunt (“fictitious deity represented as being worshipped by Muslims; any pagan god”), from Anglo-Norman Tervagant, Tervagaunt, Tervagan, and Old French Tervagant, Tervagan (possibly with the addition of Anglo-Norman -aunt, Old French -ant (suffix forming present participles of verbs, some of which were used as nouns); modern French Tervagant (historical)); further etymology uncertain, one common suggestion being that it is from Latin ter (“three times, thrice”) (ultimately from Proto-Indo-European *tréyes (“three”)) + vagāns (“rambling, wandering”) (the present active participle of vagor (“to ramble, roam, wander”), from vagus (“rambling, roaming, wandering”) (possibly ultimately from Proto-Indo-European *Hwogos) + -or (inflected form of -ō (suffix forming regular first-conjugation verbs)). Medieval French chansons de geste named Termagant as one of three deities supposedly worshipped by Muslims, the others being Apollin and Mahound, and the name may allude to the wandering of the moon (the crescent moon being a common symbol of Islam) in the form of the mythological goddesses Selene in heaven, Diana on earth, and Proserpina in the underworld. The reason for the shift in meaning from the fictitious deity to a brawling and turbulent person is unclear. The adjective is derived from the noun.

PIE word *tréyes The noun is derived from Termagant (“fictitious deity with a violent temperament represented as being worshipped by Muslims or other non-Christians”), from Middle English Termagaunt (“fictitious deity represented as being worshipped by Muslims; any pagan god”), from Anglo-Norman Tervagant, Tervagaunt, Tervagan, and Old French Tervagant, Tervagan (possibly with the addition of Anglo-Norman -aunt, Old French -ant (suffix forming present participles of verbs, some of which were used as nouns); modern French Tervagant (historical)); further etymology uncertain, one common suggestion being that it is from Latin ter (“three times, thrice”) (ultimately from Proto-Indo-European *tréyes (“three”)) + vagāns (“rambling, wandering”) (the present active participle of vagor (“to ramble, roam, wander”), from vagus (“rambling, roaming, wandering”) (possibly ultimately from Proto-Indo-European *Hwogos) + -or (inflected form of -ō (suffix forming regular first-conjugation verbs)). Medieval French chansons de geste named Termagant as one of three deities supposedly worshipped by Muslims, the others being Apollin and Mahound, and the name may allude to the wandering of the moon (the crescent moon being a common symbol of Islam) in the form of the mythological goddesses Selene in heaven, Diana on earth, and Proserpina in the underworld. The reason for the shift in meaning from the fictitious deity to a brawling and turbulent person is unclear. The adjective is derived from the noun.