catastrophe vs calamity

catastrophe and calamity both are nouns.

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

As nouns, catastrophe and calamity are synonyms defined as:

catastrophe and calamity: an event resulting in great loss and misfortune

Other synonyms of catastrophe include cataclysm, disaster, tragedy.

catastrophe (noun)	calamity (noun)
an event resulting in great loss and misfortune	an event resulting in great loss and misfortune
a sudden violent change in the earth's surface
a state of extreme (usually irremediable) ruin and misfortune