disastrous vs calamitous

disastrous and calamitous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
disastrous	No	Yes	No	No
calamitous	No	Yes	No	No

As adjectives, disastrous and calamitous are synonyms defined as:

disastrous and calamitous: (of events) having extremely unfortunate or dire consequences; bringing ruin

Other synonyms of disastrous include black, fatal, fateful.

disastrous (adjective)	calamitous (adjective)
(of events) having extremely unfortunate or dire consequences; bringing ruin	(of events) having extremely unfortunate or dire consequences; bringing ruin