calamity vs misfortune

calamity and misfortune both are nouns.

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

As nouns, misfortune is a hypernym of calamity; that is, misfortune is a word with a broader meaning than calamity:

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

Other hypernyms of calamity include bad luck.

calamity (noun)	misfortune (noun)
an event resulting in great loss and misfortune	unnecessary and unforeseen trouble resulting from an unfortunate event
	an unfortunate state resulting from unfavorable outcomes