incantation

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Ritual recitation of verbal charms or spells to produce a magic effect.
• noun A formula used in ritual recitation; a verbal charm or spell.
• noun A conventionalized utterance repeated without thought or aptness; a formula.

from The Century Dictionary.

• noun The art or act of enchanting by uttering magical words, with ceremonies supposed to have magical power; also, the formula of words or the ceremony employed.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act or process of using formulas sung or spoken, with occult ceremonies, for the purpose of raising spirits, producing enchantment, or affecting other magical results; enchantment.
• noun A formula of words used as above.
• noun The repetitive invoking of old sayings, or emitting a wordy discourse with little or no meaning, to avoid serious discussion; obfuscation.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The act or process of using formulas and/or usually rhyming words, sung or spoken, with occult ceremonies, for the purpose of raising spirits, producing enchantment, or creating other magical results.
• noun A formula of words used as above.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a ritual recitation of words or sounds believed to have a magical effect