scream vs screak

scream is a noun but screak is not a noun.

Word	Noun	Adjective	Verb	Adverb
scream	Yes	No	Yes	No
screak	No	No	Yes	No

As verbs, screak is a hyponym of scream; that is, screak is a word with a more specific, narrower meaning than scream:

scream (noun)	screak (noun)
sharp piercing cry
a joke that seems extremely funny
a high-pitched noise resembling a human cry

scream (verb)	screak (verb)
utter a sudden loud cry	utter a harsh abrupt scream
utter or declare in a very loud voice	make a high-pitched, screeching noise
make a loud, piercing sound