chimerical

chimerical \ky-MER-ih-kuhl; -MIR-; kih-\, adjective:

1. Merely imaginary; produced by or as if by a wildly fanciful imagination; fantastic; improbable or unrealistic.
2. Given to or indulging in unrealistic fantasies or fantastic schemes.

But those risks are real, not chimerical.
-- George J. Church, "Mission of Mercy", Time, April 29, 1991

It prophesies war in the service of a peace which can never arrive because the vision it pursues is chimerical.
-- Hywel Williams, "The danger of liberal imperialism", The Guardian, October 4, 2001

In the chimerical atmosphere of the Museum of Jurassic Technology, it is far from clear where fact ends and fiction begins--or vice versa.
-- Margaret Wertheim, "The Museum of Jurassic Technology", Omni, November 1, 1994

Her name is Dulcinea; her country El Toboso, a village in La Mancha; her degree at least that of Princess, for she is my Queen and mistress; her beauty superhuman, for in her are realized all the impossible and chimerical attributes of beauty which poets give to their ladies.
-- Miguel De Cervantes, Don Quixote

Chimerical is ultimately derived from Greek khimaira, "she-goat" or "chimera," which in Greek mythology was a monster having the head of a lion, the body of a goat, and the tail of a dragon.

Dictionary.com Entry and Pronunciation for chimerical