fairyland vs paracosm

fairyland and paracosm both are nouns.

Word	Noun	Adjective	Verb	Adverb
fairyland	Yes	No	No	No
paracosm	Yes	No	No	No

As nouns, paracosm is a hyponym of fairyland; that is, paracosm is a word with a more specific, narrower meaning than fairyland:

fairyland: something existing solely in the imagination (but often mistaken for reality)
paracosm: a prolonged fantasy world invented by children; can have a definite geography and language and history

fairyland (noun)	paracosm (noun)
something existing solely in the imagination (but often mistaken for reality)	a prolonged fantasy world invented by children; can have a definite geography and language and history
the enchanted realm of fairies