sound off vs squawk

sound off is not a noun while squawk is a noun.

Word	Noun	Adjective	Verb	Adverb
sound off	No	No	Yes	No
squawk	Yes	No	Yes	No

As verbs, squawk is a hyponym of sound off; that is, squawk is a word with a more specific, narrower meaning than sound off:

sound off (noun)	squawk (noun)
	informal terms for objecting
	the noise of squawking

sound off (verb)	squawk (verb)
express complaints, discontent, displeasure, or unhappiness	complain
express one's opinion openly and without fear or hesitation	utter a harsh abrupt scream
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