quietude vs tranquillity

quietude and tranquillity both are nouns.

Word	Noun	Adjective	Verb	Adverb
quietude	Yes	No	No	No
tranquillity	Yes	No	No	No

As nouns, quietude and tranquillity are synonyms defined as:

Other synonyms of quietude include quietness, tranquility.

quietude (noun)	tranquillity (noun)
a state of peace and quiet	a disposition free from stress or emotion
	a state of peace and quiet
	an untroubled state; free from disturbances