dreamworld vs imaginary place

dreamworld and imaginary place both are nouns.

Word	Noun	Adjective	Verb	Adverb
dreamworld	Yes	No	No	No
imaginary place	Yes	No	No	No

As nouns, imaginary place is a hypernym of dreamworld; that is, imaginary place is a word with a broader meaning than dreamworld:

dreamworld: a pleasing country existing only in dreams or imagination
imaginary place: a place that exists only in imagination; a place said to exist in fictional or religious writings

Other hypernyms of dreamworld include fictitious place, mythical place.

dreamworld (noun)	imaginary place (noun)
a pleasing country existing only in dreams or imagination	a place that exists only in imagination; a place said to exist in fictional or religious writings