Definition of fantasy noun from the Oxford Advanced Learner's Dictionary

fantasy

noun
ˈfæntəsi
 
; ˈfæntəsi
 
plural fantasies
 
1 [countable] a pleasant situation that you imagine but that is unlikely to happenhis childhood fantasies about becoming a famous football player2 [countable] a product of your imaginationHer books are usually escapist fantasies.3 [uncountable] the act of imagining things; a person's imaginationa work of fantasyStop living in a fantasy world.