Abraxas (Gr. or ), a mystical word employed by the Egyptian Gnostic Basil-ides to signify the Supreme Being as ruler of the 365 heavens of his system, which number is represented by its letters according to Greek numeration; probably in imitation of the significance attached to the name of the Persian god Mithras the letters of which have the same numerical value. Some authorities, however, give the word other derivations and different significations as a designation of the Supreme Being. - Many ancient stones or metallic tablets called Abraxas gems or images, or Basilidian stones, have been found, chiefly in Egypt, Syria, and Spain. They are generally inscribed with the word Abraxas or Abrasax, and sometimes with others, and bear a great variety of Gnostic and other mystical symbols, occasionally perhaps merely natural markings. They were used as amulets, and supposed to be endued with miraculous qualities.