shrill vs shriek

shrill is not a noun while shriek is a noun.

Word	Noun	Adjective	Verb	Adverb
shrill	No	Yes	Yes	No
shriek	Yes	No	Yes	No

As verbs, shrill and shriek are synonyms defined as:

Other synonyms of shrill include pipe, pipe up.

shrill (noun)	shriek (noun)
	sharp piercing cry
	a high-pitched noise resembling a human cry

shrill (adjective)	shriek (adjective)
of colors that are bright and gaudy
having or emitting a high-pitched and sharp tone or tones
being sharply insistent on being heard

shrill (verb)	shriek (verb)
utter a shrill cry	utter a shrill cry