force majeure vs calamity

force majeure and calamity both are nouns.

Word	Noun	Adjective	Verb	Adverb
force majeure	Yes	No	No	No
calamity	Yes	No	No	No

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

force majeure: a natural and unavoidable catastrophe that interrupts the expected course of events
calamity: an event resulting in great loss and misfortune

Other hypernyms of force majeure include cataclysm, catastrophe, disaster, tragedy.

force majeure (noun)	calamity (noun)
a natural and unavoidable catastrophe that interrupts the expected course of events	an event resulting in great loss and misfortune