misfortune vs disaster

misfortune and disaster both are nouns.

Word	Noun	Adjective	Verb	Adverb
misfortune	Yes	No	No	No
disaster	Yes	No	No	No

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

misfortune: unnecessary and unforeseen trouble resulting from an unfortunate event
disaster: an event resulting in great loss and misfortune

misfortune (noun)	disaster (noun)
unnecessary and unforeseen trouble resulting from an unfortunate event	an act that has disastrous consequences
an unfortunate state resulting from unfavorable outcomes	an event resulting in great loss and misfortune
	a state of extreme (usually irremediable) ruin and misfortune