calmness vs quiet

calmness and quiet both are nouns.

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

As nouns, quiet is a hyponym of calmness; that is, quiet is a word with a more specific, narrower meaning than calmness:

As nouns, quiet is a hyponym of calmness; that is, quiet is a word with a more specific, narrower meaning than calmness:

Other hyponyms of calmness include stillness, windlessness, lull.

calmness (noun)	quiet (noun)
steadiness of mind under stress	a disposition free from stress or emotion
a feeling of calm; an absence of agitation or excitement	the absence of sound
an absence of strong winds or rain	a period of calm weather
	an untroubled state; free from disturbances

calmness (adjective)	quiet (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

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

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