[1] : The Collaborative International Dictionary of English v.0.48

daydream \day"dream`\ -dr=em`, n.
   a vain fancy speculation; a reverie; a castle in the air;
   unfounded hope.
   1913 webster

         mrs. lambert's little daydream was over. --thackeray.
   1913 webster

[2] : WordNet (r) 2.0

daydream
     n : absent-minded dreaming while awake syn: reverie, revery,
          daydreaming, oneirism, air castle, castle in the
         air, castle in spain
     v 1: have a daydream; indulge in a fantasy syn: dream, woolgather,
           stargaze
     2: have dreamlike musings or fantasies while awake; "she looked
        out the window, daydreaming" syn: moon
see also:
reverie revery daydreaming oneirism air castle castle in the air 
castle in spain dream woolgather stargaze moon 

[3] : Moby Thesaurus II by Grady Ward, 1.0

79 moby thesaurus words for "daydream":
   walter mitty, absence of mind, absentmindedness, absorption,
   abstractedness, abstraction, airy nothing, autism, bad dream,
   be absent, bemusement, brown study, bubble, castle-building,
   chimera, conceiving, daydreamer, daydreaming, deception,
   deluded belief, delusion, depth of thought, dereism, divagate,
   dream, dream of, dream vision, dreaming, dreamland, dreamworld,
   engrossment, false belief, fantasy, fantasying, fit of abstraction,
   freak out, go woolgathering, ignis fatuus, illusion, imagination,
   imagining, incubus, misbelief, misconception, moon, mooning,
   moonraking, muse, musefulness, musing, muted ecstasy, nightmare,
   nostalgia, phantasm, pipe dream, pipe-dream, pipe-dreaming,
   preoccupation, reverie, self-deceit, self-deception, self-delusion,
   stargaze, stargazing, stray, study, trance, trick, trip, vapor,
   vision, wander, wishful thinking, wishfulness, wistful eye,
   wistfulness, woolgathering, wrong impression, yearnfulness

Daydream >> D Words
Daydream, definition of term: Daydream
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