Synonyms for Unreal (same or very similar meaning)
WordNet sense 1 (resembling a dream):
dreamlike
WordNet sense 2 (based on or having the nature of an illusion):
illusory
WordNet sense 3 (marked by or producing illusion):
illusionary
WordNet sense 4 (not based on fact; dubious):
fanciful, imaginary
WordNet sense 5 (based on or told of in traditional stories; lacking factual basis or historical validity):
fabulous, mythical
WordNet sense 6 (formed or conceived by the imagination):
fictitious
WordNet sense 7 (celebrated in fable or legend):
legendary
WordNet sense 8 (not genuine or real; being an imitation of the genuine article):
false
WordNet sense 9 (contrived by art rather than nature):
artificial
WordNet sense 10 (lacking in substance):
shadowy
WordNet sense 11 (characterized by lightness and insubstantiality; as impalpable or intangible as air):
aerial, aerial
WordNet sense 12 (lacking material form or substance; unreal):
insubstantial, unsubstantial
From the ODE community, based on WordNet
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