Q: Where did ''abracadabra,'' a word commonly used by amateur magicians, come from?

H. Rosenfeld,

Miami

A: According to the Oxford English Dictionary, abracadabra is ''a meaningless word of mysterious sound.'' Nevertheless, it has a long history. Its first recorded appearance is in a poem written in the second century by Quintus Sammonicus Serenus, physician to the Roman emperor Caracalla. Since it contains various medical remedies of the day, the poem served as a teaching tool.

The OED notes that abracadabra was an incantation to be inscribed on an amulet in the form of an inverted triangle and was worn about the neck to keep fever and other maladies at bay.

The origin of the word, though, is unknown; it may have come from Aramaic, Christ's native tongue, or Hebrew. Another theory is that it's related to the word ''Abraxas,'' derived from the Ancient Greek word for ''god.'' In the Ancient Greek numerology system, which originated with Pythagoras more than 500 years before Christ's birth, the value of Abraxas indicated it could ward off evil.

From the earliest times, all societies have believed that words, if spoken in a prescribed manner, possess magical or sacred qualities, and for that reason, incantations, spells, spoken rituals or prayers change little as they pass down through generations. Whatever its origin, since its use by Roman citizens 1,800 years ago, the ''abracadabra'' spell seems to have arrived in the 21st Century little changed.