Wordnet 3.0
ADJECTIVE (1)
1. 
 not realistic; 
- Example: "unrealistic expectations"- Example: "prices at unrealistic high levels"
WordNet (r) 3.0 (2006):
unrealistic
    adj 1: not realistic; "unrealistic expectations"; "prices at
           unrealistic high levels" [ant: realistic]
Moby Thesaurus II by Grady Ward, 1.0:
39 Moby Thesaurus words for "unrealistic":
   airy, autistic, delusional, delusive, delusory, dereistic,
   fanciful, idealistic, illogical, illusory, imaginary, immaterial,
   impractical, in the clouds, inaccurate, merely nominal, not real,
   otherworldly, poetic, quixotic, romancing, romantic, romanticized,
   starry-eyed, storybook, transcendental, transmundane, unactual,
   unauthentic, unnatural, unpractical, unreal, unrealizable,
   unreasonable, unrepresentative, unsubstantial, unworkable,
   visionary, wish-fulfilling