imagery vs dream

imagery and dream both are nouns.

Word	Noun	Adjective	Verb	Adverb
imagery	Yes	No	No	No
dream	Yes	No	Yes	No

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

imagery (noun)	dream (noun)
the ability to form mental images of things or events	a series of mental images and emotions occurring during sleep
	imaginative thoughts indulged in while awake
	a fantastic but vain hope (from fantasies induced by the opium pipe)
	a state of mind characterized by abstraction and release from reality
	a cherished desire
	someone or something wonderful

imagery (verb)	dream (verb)
	have a daydream; indulge in a fantasy
	experience while sleeping