Exorcism is 1) the driving out, or warding off demons, or evilspirits, from persons, places, or things which are believed to bepossessed by them, or are liable to become victims of theirmalice; 2) the means used for this purpose, especially the solemn and authoritative  of  adjuration of the demon, in the name ofGod, or some other higher power.

The word is derived from exorkizo (Greek: Expulsion byadjuration) It is used in Matthew 26:63, by the high priest to Christ, "I adjure thee by the living God. . ." Also in Acts 19:13, where it is applied to certain Jews who professed to be able to cast out demons. In Christian usage, the priest uses holy water, holy oil and the crucifix,  and uses the names of God or Christ to order the demon to leave.

The exorcisms of other systems also rely on the use of magical
 words, names and symbols.

The ancient Egyptiansascribed certain diseases and various other evils to the work of demons, and used magical charms and incantations to banish or dispel them.

Babylonian exorcism was a part of medical treatment and largely dealt with certain diseases thought to be caused by demon possession.  Exorcism was thought to be the easiest, if not the only, way of curing them.  Just as in Christian exorcism, the name of some god or goddess, or some group of deities, was invoked to adjure the demon away and repair the damage he had caused. Thusly: "O, demon who has seized this man, O, demon who has seized this man. O, demon who works harm, evil demon, I conjure O, spirit of heaven; I conjure O, spirit of earth."

In the Old Testament, there are not accounts of exorcisms by men, but other Jewish writing refer to exorcisms.  The chief characteristics of these exorcisms is their naming of the names of good angels, which are used either alone or in combination with El (God). Reliance on these names is an ancient practice of the Jews, who considered it most important that the appropriate names, which varied for different times and occasions, should be used. It may have been this practyice, that prompted the sons of Sceva, who had witnessed St. Paul's successful exorcisms in the name of Jesus, to try on their own account the formula, "I conjure you by Jesus whom Paul preacheth"." According to the record, this did not work out well. The historian Josephus said that King Solomon had received the power of expelling demons, and that he had composed and transmitted certain formulæ that were efficacious for that purpose. He also records how a certain Eleazar, in the presence of the Emperor Vespasian and his officers, used a magical ring applied to the nose of a possessed person, to draw out the demon through the nostrils — the power of the ring rested in the fact that it contained a certain rare root mentioned in the formulaæ of  King Solomon, and which it was very rare.