The Oxford Thesaurus An A-Z Dictionary of Synonyms - unrealisticadj.

1) impractical, illogical, unreasonable, unworkable, unrealizable, quixotic, romantic, fanciful, visionary, delusional, delusive, delusory: However exciting it is to think of travelling faster than light, the notion is unrealistic. 2) unreal, unlifelike, unnatural, unauthentic, non-representational, unrepresentative, inaccurate: The background paintings are poorly done and unrealistic.