abraxas

from The Century Dictionary.

• noun In antiquity, a Gnostic amulet consisting of an engraved gem, often bearing a mystical figure (which generally combines human and brute forms) and an unintelligible legend, but sometimes inscribed with the word Abraxas, either alone or accompanying a figure or a word connected with Hebrew or Egyptian religion, as Iao, Sabaoth, Osiris. A mystical word used by the Gnostic followers of Basilides to denote the Supreme Being, or, perhaps, its 365 emanations collectively, or the 365 orders of spirits occupying the 365 heavens.
• noun Also written Abrasax.
• noun A genus of lepidopterous insects, of the family Geometridæ, containing the large magpie-moth, Abraxas grossulariata.

from the GNU version of the Collaborative International Dictionary of English.

• noun A mystical word used as a charm and engraved on gems among the ancients; also, a gem stone thus engraved.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Gnosticism, historical A mistaken transcription of Abrasax.