cataclysm vs tragedy

cataclysm and tragedy both are nouns.

Word	Noun	Adjective	Verb	Adverb
cataclysm	Yes	No	No	No
tragedy	Yes	No	No	No

As nouns, cataclysm and tragedy are synonyms defined as:

Other synonyms of cataclysm include calamity, catastrophe, disaster.

cataclysm (noun)	tragedy (noun)
an event resulting in great loss and misfortune	drama in which the protagonist is overcome by some superior force or circumstance; excites terror or pity
a sudden violent change in the earth's surface	an event resulting in great loss and misfortune