quieten vs silence

quieten is not a noun while silence is a noun.

Word	Noun	Adjective	Verb	Adverb
quieten	No	No	Yes	No
silence	Yes	No	Yes	No

As verbs, quieten and silence are synonyms defined as:

Other synonyms of quieten include hush, hush up, shut up, still.

quieten (noun)	silence (noun)
	the absence of sound
	a refusal to speak when expected
	the trait of keeping things secret
	the state of being silent (as when no one is speaking)

quieten (verb)	silence (verb)
cause to be quiet or not talk	cause to be quiet or not talk
make calm or still	keep from expression, for example by threats or pressure
become quiet or quieter