knife vs sticker

knife and sticker both are nouns.

Word	Noun	Adjective	Verb	Adverb
knife	Yes	No	Yes	No
sticker	Yes	No	No	No

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

Other hyponyms of knife include bayonet, dagger, khukuri, machete, matchet, panga, shiv, trench knife, yataghan, kindjal, seax.

knife (noun)	sticker (noun)
edge tool used as a cutting instrument; has a pointed blade with a sharp edge and a handle	a short knife with a pointed blade used for piercing or stabbing
a weapon with a handle and blade with a sharp point	an adhesive label
any long thin projection that is transient	a particularly difficult or baffling question or problem
	a small sharp-pointed tip resembling a spike on a stem or leaf

knife (verb)	sticker (verb)
use a knife on