dashing hopes vs disappointment

dashing hopes and disappointment both are nouns.

Word	Noun	Adjective	Verb	Adverb
dashing hopes	Yes	No	No	No
disappointment	Yes	No	No	No

As nouns, dashing hopes and disappointment are synonyms defined as:

dashing hopes and disappointment: an act (or failure to act) that disappoints someone

dashing hopes (noun)	disappointment (noun)
an act (or failure to act) that disappoints someone	an act (or failure to act) that disappoints someone
	a feeling of dissatisfaction that results when your expectations are not realized