The Collaborative International Dictionary of English v.0.48:

Fantasy \Fan"ta*sy\, n.; pl. Fantasies. [See Fancy.]
   1. Fancy; imagination; especially, a whimsical or fanciful
      conception; a vagary of the imagination; whim; caprice;
      humor.
      [1913 Webster]

            Is not this something more than fantasy ? --Shak.
      [1913 Webster]

            A thousand fantasies
            Begin to throng into my memory.       --Milton.
      [1913 Webster]

   2. Fantastic designs.
      [1913 Webster]

            Embroidered with fantasies and flourishes of gold
            thread.                               --Hawthorne.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Fantasy \Fan"ta*sy\, v. t.
   To have a fancy for; to be pleased with; to like; to fancy.
   [Obs.] --Cavendish.
   [1913 Webster]

         Which he doth most fantasy.              --Robynson
                                                  (More's
                                                  Utopia).
   [1913 Webster] Fantigue

WordNet (r) 3.0 (2006):

fantasy
    n 1: imagination unrestricted by reality; "a schoolgirl fantasy"
         [syn: fantasy, phantasy]
    2: fiction with a large amount of imagination in it; "she made a
       lot of money writing romantic fantasies" [syn: fantasy,
       phantasy]
    3: something many people believe that is false; "they have the
       illusion that I am very wealthy" [syn: illusion, fantasy,
       phantasy, fancy]
    v 1: indulge in fantasies; "he is fantasizing when he says he
         plans to start his own company" [syn: fantasy,
         fantasize, fantasise]

Moby Thesaurus II by Grady Ward, 1.0:

230 Moby Thesaurus words for "fantasy":
   Marchen, Walter Mitty, Western, Western story, Westerner,
   absence of mind, absentmindedness, absorption, abstractedness,
   abstraction, adventure story, alienation, allegory, apologue,
   apparition, appearance, ardor, autism, autistic thinking,
   avoidance mechanism, be absent, bedtime story, bemusement,
   bizarrerie, blame-shifting, boutade, brainchild, brainstorm,
   brown study, bubble, capriccio, caprice, castle-building, chimera,
   compensation, conceit, conceiving, concoction, concupiscence,
   crank, craze, crazy idea, creativity, crotchet, curiosity,
   daydream, daydreamer, daydreaming, decompensation,
   defense mechanism, delirium, delusion, depth of thought, dereism,
   dereistic thinking, desideration, desire, detective story,
   displacement, dissociation, divagate, dream, dream of, dreaming,
   drive, eagerness, eidolon, emotional insulation, enchantment,
   engrossment, envisioning, escape, escape into fantasy,
   escape mechanism, escapism, fable, fabliau, fad, fairy tale, fancy,
   fantasizing, fantasque, fantastic notion, fantasticism, fantasying,
   ferlie, fiction, figment, figure, fit of abstraction, flight,
   flight of fancy, flimflam, folk story, folktale, fool notion, form,
   freak, freak out, freakish inspiration, fumes of fancy, gest,
   ghost story, go woolgathering, grotesquerie, hallucination,
   harebrained idea, hope, horme, horse opera, humor, idle fancy,
   idolum, illusion, image, imagery, imagination, imaginativeness,
   imagining, insubstantial image, intellectual curiosity, invention,
   inventiveness, isolation, kink, legend, libido, love story,
   lust for learning, maggot, make-believe, masquerade, megrim, mind,
   miracle, mirage, moon, mooning, moonraking, muse, musefulness,
   musing, muted ecstasy, mystery, mystery story, myth, mythology,
   mythos, need, negativism, nightmare, notion, nursery tale,
   originality, overcompensation, parable, passing fancy, passion,
   phantasm, phantasma, phantasmagoria, phantom, pipe, pipe dream,
   pipe-dream, pipe-dreaming, pleasure, pleasure principle,
   preoccupation, presence, prodigy, projection, psychotaxis, quirk,
   rainbow, rationalization, resistance, reverie, romance,
   science fiction, sexual desire, shade, shadow, shape, shocker,
   sick fancy, sign, sociological adjustive reactions, space fiction,
   space opera, specter, stargaze, stargazing, stray, study,
   sublimation, substitution, suspense story, thick-coming fancies,
   thirst for knowledge, thriller, toy, trance, trip, urge, vagary,
   vapor, vision, waking dream, wander, want, wanting, whim,
   whim-wham, whimsy, whodunit, wildest dream, wildest dreams, will,
   will and pleasure, wish, wish fulfillment,
   wish-fulfillment fantasy, wishful thinking, withdrawal, wonder,
   wonderwork, woolgathering, work of fiction, wraith