fantasy

Fantasy is a product of the imagination, particularly one that is extravagant. (noun)

An example of fantasy is a daydream to be the owner of a chain of restaurants one day.

See fantasy in Webster's New World College Dictionary

noun pl. fantasies

imagination or fancy; esp., wild, visionary fancy
an unnatural or bizarre mental image; illusion; phantasm
an odd notion; whim; caprice
1. a work of fiction portraying highly imaginative (sense ) characters or settings that have no counterparts in the real world
2. such works, collectively, as a literary form; specif., those works dealing with dragons, elves, ghosts, etc.
Music fantasia (sense )
Psychol.
1. a more-or-less connected series of mental images, as in a daydream, usually involving some unfulfilled desire
2. the activity of forming such images

to form fantasies about

intransitive verb

to indulge in fantasies, as by daydreaming

adjective

of or like a fantasy
of or pertaining to any of various games in which scoring is keyed statistically to the performances of actual players in a sport

See fantasy in American Heritage Dictionary 4

(fănˈtə-sē, -zē)

noun pl. fan·ta·sies

The creative imagination; unrestrained fancy. See Synonyms at imagination.
Something, such as an invention, that is a creation of the fancy.
A capricious or fantastic idea; a conceit.
a. Fiction characterized by highly fanciful or supernatural elements.
b. An example of such fiction.
An imagined event or sequence of mental images, such as a daydream, usually fulfilling a wish or psychological need.
An unrealistic or improbable supposition.
Music See fantasia.
A coin issued especially by a questionable authority and not intended for use as currency.
Obsolete A hallucination.