The Word of the Aeon

Abrahadabra is a word coined by Aleister Crowley, who respelled the ancient magical word abracadabra with a d in place of its second c to yield an eleven-lettered form he invested with elaborate significance. In his system of Thelema it is presented as a key word of the new age he proclaimed, the word of the Aeon, its eleven letters and their arrangement read through numerical and symbolic correspondences as expressing the union of opposites, of the human and the divine, the microcosm and the macrocosm, that his teaching sought.

The older abracadabra from which he formed it was a genuine word of ancient magic, written in a diminishing triangular pattern and worn as an amulet against fever, attested in a late-antique medical text. Crowley's reworking is characteristic of his method of taking traditional magical material and recasting it within the framework of his own revealed system, and Abrahadabra holds a central place in Thelemic symbolism.