Barbarous names is a common term for words used in many traditional rituals. The term comes from the ancient Greeks, for whom barbaroi (source of barbarous) meant anyone not speaking Greek. Barbarous names were non-sensible words that had power in magical rituals.
These words originated from different sources such as religion and magical terminology of ancient Egypt, Hebrew, and Persia. The origins of some words are cannot be traced and attempts of deciphering are of little benefit because many words have been reformed and distorted throughout the centuries. Interesting is the fact this distortion is found both in ancient and recent sources; many spells in the Greco-Egyptian magical papyi contain barbarous names that defy interpretation.
Examples of ancient barbarous names are ablanathanalba, sesengenbarpharanges, akrammachamarei. By the Middle Ages shorter names from Greek and Hebrew were preferred and commonly used, such asanexhexeton, baldachia, and anaboria.
In the current magic renaissance barbarous names have lost their importance (or glamour), although some are still found in traditional magical rituals such as the Bornless One and the Goetia as written by Aliester Crowley. The Enochian language used in Enochian Magic practiced by Elizabethan occultists John Dee and Edward Kelly still provides a major source of barbarous names.
It is taught in magical theory, ancient and current, that the importance of barbarous names resides in the sound, not their meaning. Classical theorists such as Iamblichus of Chalcis instruct their students not to decipher the names or terms, even when deciphering is possible, but to concentrate on the sound instead. The practicing of the sonorous thunder of barbarous names adds much to the psychological and magical effect of the ritual. A.G.H.
Greer, John Michael. The New Encyclopedia of the Occult. St. Paul. MN. Llewellyn Worldwide. 2005. pp. 58-59