kiss of death vs disaster

kiss of death and disaster both are nouns.

Word	Noun	Adjective	Verb	Adverb
kiss of death	Yes	No	No	No
disaster	Yes	No	No	No

As nouns, disaster is a hypernym of kiss of death; that is, disaster is a word with a broader meaning than kiss of death:

Other hypernyms of kiss of death include calamity, cataclysm, catastrophe, tragedy.

kiss of death (noun)	disaster (noun)
something that is ruinous	an act that has disastrous consequences
	an event resulting in great loss and misfortune
	a state of extreme (usually irremediable) ruin and misfortune