fantasy vs fiction

fantasy and fiction both are nouns.

Word	Noun	Adjective	Verb	Adverb
fantasy	Yes	No	Yes	No
fiction	Yes	No	No	No

As nouns, fiction is a hypernym of fantasy; that is, fiction is a word with a broader meaning than fantasy:

fantasy: fiction with a large amount of imagination in it
fiction: a literary work based on the imagination and not necessarily on fact

fantasy (noun)	fiction (noun)
imagination unrestricted by reality	a literary work based on the imagination and not necessarily on fact
something many people believe that is false	a deliberately false or improbable account
fiction with a large amount of imagination in it

fantasy (verb)	fiction (verb)
indulge in fantasies