The word derives from the Hebrew abreg ad habra meaning to 'strike dead with thy lightning.' In Hebrew it comprises nine letters. 'Placing aleph on the left side of the triangle - and its ninefold repetition - is the magical element.' By arranging the letters in a reverse triangle, the celestial energies which the charm claims to entrap are directed downwards. According, the figure should be seen three-dimensionally as a funnel. Like amulets, talismans and pentacles, this charm seeks to give the individual a sense of protection through communication with the higher powers and with the mysterious laws which govern the universe.
from THE PENGUIN DICTIONARY OF SYMBOLS
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