Abraxas, or Abrasax, was a word engraved on certain antique stones, called on that account Abraxas stones, which were used as amulets or charms by Gnostic sects.
Abraxas was an Archon with a chimera-like appearance: he had the head of a rooster, the body of a man, and legs fashioned like snakes. Abraxas was redeemed and rose above the seven spheres and now reigns beyond the worlds. There are references to Abraxas in several gnostic writings.
The letters of abraxas, in the Greek notation, make up the number 365, and the Basilidians gave the name to the 365 orders of spirits which, as they conceived, emanated in succession from the Supreme Being.
These orders were supposed to occupy 365 heavens, each fashioned like, but inferior to that above it; and the lowest of the heavens was thought to be the abode of the spirits who formed Earth and its inhabitants, and to whom was committed the administration of its affairs.
Abraxas stones are of very little value. In addition to the word Abraxas and other mystical characters, they have often cabalistic figures engraved on them. The commonest of these have the head of a fowl, and the arms and bust of a man, and terminate in the body and tail of a serpent.
Initial text from 1911 encyclopedia.
Abraxas is also the name of a god, like the Christian God, but not omnibenevolent.