The Collaborative International Dictionary of English v.0.48:

Incantation \In`can*ta"tion\, n. [L. incantatio, fr. incantare
   to chant a magic formula over one: cf. F. incantation. See
   Enchant.]
   [1913 Webster]
   1. 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. "Mysterious ceremony and incantation."
      --Burke.
      [1913 Webster]

   2. A formula of words used as above.
      [1913 Webster]

   3. The repetitive invoking of old sayings, or emitting a
      wordy discourse with little or no meaning, to avoid
      serious discussion; obfuscation; as, to defend one's views
      with empty incantations.
      [PJC]

Jargon File (4.4.4, 14 Aug 2003):

incantation
 n.

   Any particularly arbitrary or obscure command that one must mutter at
   a system to attain a desired result. Not used of passwords or other
   explicit security features. Especially used of tricks that are so
   poorly documented that they must be learned from a wizard. "This
   compiler normally locates initialized data in the data segment, but
if
   you mutter the right incantation they will be forced into text
   space."


Moby Thesaurus II by Grady Ward, 1.0:

22 Moby Thesaurus words for "incantation":
   abracadabra, bewitchment, conjuration, conjurement, devil,
   enchantment, evocation, exorcisation, exorcism, exsufflation,
   hocus-pocus, invocation, magic formula, magic words, mumbo jumbo,
   necromancy, open sesame, rune, sorcery, witchcraft, witchery,
   wizardry