silence vs still

silence and still both are nouns.

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

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

Other hyponyms of silence include hush, stillness, speechlessness, quietness, soundlessness.

As verbs, silence and still are synonyms defined as:

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

silence (noun)	still (noun)
the absence of sound	an apparatus used for the distillation of liquids; consists of a vessel in which a substance is vaporized by heat and a condenser where the vapor is condensed
a refusal to speak when expected	a static photograph (especially one taken from a movie and used for advertising purposes)
the trait of keeping things secret	a plant and works where alcoholic drinks are made by distillation
the state of being silent (as when no one is speaking)	(poetic) tranquil silence

silence (adjective)	still (adjective)
	not sparkling
	used of pictures; of a single or static photograph not presented so as to create the illusion of motion; or representing objects not capable of motion
	(of a body of water) free from disturbance by heavy waves
	marked by absence of sound
	not in physical motion
	free from noticeable current

silence (verb)	still (verb)
cause to be quiet or not talk	cause to be quiet or not talk
keep from expression, for example by threats or pressure	make motionless
	make calm or still
	lessen the intensity of or calm

silence (adverb)	still (adverb)
	to a greater degree or extent; used with comparisons
	with reference to action or condition; without change, interruption, or cessation
	without moving or making a sound
	despite anything to the contrary (usually preceding a concession)