quiet vs tranquillity

quiet and tranquillity both are nouns.

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

As nouns, quiet and tranquillity are synonyms defined as:

Other synonyms of quiet include placidity, repose, serenity, tranquility.

As nouns, quiet and tranquillity are synonyms defined as:

Other synonyms of quiet include tranquility.

quiet (noun)	tranquillity (noun)
a disposition free from stress or emotion	a disposition free from stress or emotion
the absence of sound	a state of peace and quiet
a period of calm weather	an untroubled state; free from disturbances
an untroubled state; free from disturbances

quiet (adjective)	tranquillity (adjective)
free of noise or uproar; or making little if any sound
characterized by an absence or near absence of agitation or activity
(of the sun) characterized by a low level of surface phenomena, such as sunspots
(of a body of water) free from disturbance by heavy waves
in a softened tone
not showy or obtrusive

quiet (verb)	tranquillity (verb)
make calm or still
become quiet or quieter

quiet (adverb)	tranquillity (adverb)
with little or no activity or no agitation (`quiet' is a nonstandard variant for `quietly')