One of the mailing lists I subscribe to is for storytellers. Recently one storyteller told about a session she was leading at a Jewish community center in Key Largo, FL. Part of her show includes a magic trick. A member of the audience went to her and said, "Did you know abracadabra came from Hebrew? It means "it is spoken and created." A Hazzan in the audience confirmed the comments. The storyteller was not satisfied and wrote to a rabbi friend, who agreed that it was possible that abracadabra came from the Aramaic, abra k'kabra, or Hebrew bara dabar,ברא דבר meaning “It is created as it is spoken.”
This is a folk etymology. Abracadabra is a magic word. Even today stage magicians use it to distract the audience while the trick is performed. The word can be traced to the Gnostic Christians of the second century. One Catholic storyteller reported that she learned never to say the word because it is associated with conjuring the devil.. Another folk etymology is the word comes from Av אב ("father") bar בר("son") ru-ah ha-kodesh הקודש רח ("holy spirit"). There is no linguistic reason to accept these explanations. Hebrew and other Semitic languages grow based on roots. Even modern words are based on Biblical roots. German grows by combining words; not Hebrew.
Let me give some of the other explanations
1) It was first mentioned in a poem by Quintus Serenus Sammonicus in the second century. It is believed to have come into English via French from a Greek word abrasadabra (the change from s to c seems to have been through a confused transliteration of the Greek). It originated as a secret and mystical word with a Gnostic sect in Alexandria called the Basilidians (named after their founder Basilides of Egypt). The word was possibly based on Abrasax, the name of an Egyptian deity. It was used as charm to cure toothaches and infectious diseases. The word Abrasax was said to have magical powers. Using the gematria 
of the Greek letters the holy names Abraxas (Άβραξάς) and Mithras (Μίθρας) the Gnostics equated the numerical values of 365, the days of the year. Because of the relationship of Abraxas to the number of days, it was frequently used on amulets and precious stones.
2) Abracadabra is based on the first four letters of the Phonecian alphabet, which preceded the square Hebrew alphabet we use today. The letters are A Bra Ca Da. This explanation makes no linguistic sense. The Hebrew alphabet is based on the Phonecian letters of the period 800-900 BCE. We call this Old Hebrew. The Greeks took over the forms of the letters and made modifications to fit the needs of their language. The Greeks also change the direction of writing from right to left to left to right. Hence some of the letters were turned around. The Romans took the Gimel and separated it to represent the G and C sounds. (In Latin the C is always pronounced as a hard /k/.) The alphabetic order put the C in third place and the G in the place of zeta which had no Latin equivalent sound. Taking the Latin letters one may write a charm. Each row loses one letter from the end.
While it seems logical that Abracadabra is from Aramaic, the word and root do not appear in Biblical Aramaic, Talmud or other early Aramaic or Hebrew sources.Language is hardly 100% logical. Joshua Trachtenberg in, Jewish Magic and Superstition (New York, 1974) says that certain words come to assume occult virtues by reason of descent from potent charms. The potency is hidden in its syllables.
Trachtenberg has a chapter, "In the Name of..." which discusses the potency of a name. Names of people are supposed to reflect a certain essence of their being. That is why parents choose names carefully and name their children for relatives. I just heard a discussion of names at a family gathering. One child was named for grandparent. The mother said that every time she sees her child she is reminded of her late grandmother. I remember the grandmother and I, too, felt her presence when the child was called. One couple was pregnant and the discussion was one what to name the child. The father wanted to remember his grandfather, whose name was Velvel. The aunt said, "How could you name a child Vevel! He will be so out of place in a modern Orthodox school."
According to Trachtenberg the name brings with it the accumulated history of all those who have owned the name in the past. This was balanced with fear that the soul of the previous owner would be transported to the baby. A fear that stands in the way of Ashkenazim from naming child after living relatives. Because certain names bring good fortune, parents should not name a child after someone who has caused misfortune. In the extreme case before World War II Adolph was used as a name. Afterwards Jews would never use that name. Knowing someone's name is to exercise a kind of power over them.
For the magician the use of mystical or magical names garners superhuman powers. The magician controls the forces of the supernatural. Therefore spiritual beings guard their names. God-fearing Jews never pronounce the Tetragramaton name of God. We do not even write the Name. In casual writing we use the letter Hey followed by an apostrophe. In printed works the name is written without vowels, with a yod-yod, or other reverent representations. The avoidance of the use of the Name reminds us that only the high priest in the Temple pronounced the Name. Today the respect for the Name is an example of pristine monotheism and kedushat haShem in its most essential sense.
Magic was always on the periphery of religion. That is one reason the rabbis forbid contact with black magic (kishshuf and lahash ).However, magic as a very conservative discipline, clung to many archaic forms long after the original meaning was lost.The magic demanded an adherence to the ancient forms of names and chants. The secret society of magicians passed on these secret words and syllables as oral tradition.
The medieval magician could have been using a word that sounded magic and had no idea what it orignally meant. My conclusion that no one knows the exact origin of abracadabra, is based on a commentary by Rashi (Babylonian Talmud, Sotah page 22a) quoted by Trachtenberg, "The sorcerer whispers his charms, and doesn't understand what they are what they mean, but ... the desired effect is produced only by these incantations."
 Gematria is a Greek word. In rabbinic literature numerical gematria first appears in statements of the tannaim of the second century. For more information see the article, "Gematria" in the Encyclopedia Judaica v. 7. Gematria according to S. Lieberman Hellenism in Jewish Palestine was a Greek invention adapted by the Semites. In the second Temple era Greek letters were used to signify numbers.
Sanhedrin 67b, Yore Deah 179:15, Rambam Sefer HaMadah, Hilkhot 'Avodah Zarah, 11:15
 Trachtenberg. P. 81.
Daniel D. Stuhlman is president of Stuhlman Management Consultants, Chicago, IL, a firm helping organizations turn data and information into knowledge. We are looking for new clients and opportunities. Visit our web site to learn more about knowledge management and what our firm can do for you. Previous issues of Librarian's Lobby can be found at: http://home.earthlink.net/~DDStuhlman/liblob.htm.©2003 by Daniel D. Stuhlman. All rights reserved.
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Last revised October 21, 2004