The Collaborative International Dictionary of English v.0.48:

thaumaturgy \thau"ma*tur`gy\ (th[add]`m[.a]*t[^u]r"j[y^]), n.
   [Gr. qaymatourgi`a.]
   The act or art of performing something wonderful; magic;
   legerdemain. --T. Warton.
   [1913 Webster]

WordNet (r) 3.0 (2006):

thaumaturgy
    n 1: any art that invokes supernatural powers [syn: magic,
         thaumaturgy]
    2: an illusory feat; considered magical by naive observers [syn:
       magic trick, conjuring trick, trick, magic,
       legerdemain, conjuration, thaumaturgy, illusion,
       deception]

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "thaumaturgy":
   alchemy, bewitchery, bewitchment, charm, divination, enchantment,
   fetishism, glamour, gramarye, hoodoo, incantation, juju, jujuism,
   magic, natural magic, necromancy, obeah, rune, shamanism, sorcery,
   sortilege, spell, spellbinding, spellcasting, sympathetic magic,
   thaumaturgia, thaumaturgics, thaumaturgism, theurgy, vampirism,
   voodoo, voodooism, wanga, white magic, witchcraft, witchery,
   witchwork, wizardry