From WordNet (r) 2.0 (August 2003) [wn]:
unreal
adj 1: lacking in reality or substance or genuineness; not
corresponding to acknowledged facts or criteria;
"ghosts and other unreal entities"; "unreal propaganda
serving as news" [ant: real]
2: not actually such; being or seeming fanciful or imaginary;
"this conversation is getting more and more unreal"; "the
fantastically unreal world of government bureaucracy";
"the unreal world of advertising art" [ant: {real(a)}]
3: contrived by art rather than nature; "artificial flowers";
"artificial flavoring"; "an artificial diamond";
"artificial fibers"; "artificial sweeteners" [syn:
artificial] [ant: natural]
4: lacking material form or substance; unreal; "as
insubstantial as a dream"; "an insubstantial mirage on the
horizon" [syn: insubstantial, unsubstantial] [ant:
substantial]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Unreal \Un*re"al\, a.
Not real; unsubstantial; fanciful; ideal.
[1913 Webster]