sound off vs scold

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

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

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

sound off (noun)	scold (noun)
	someone (especially a woman) who annoys people by constantly finding fault

sound off (verb)	scold (verb)
express complaints, discontent, displeasure, or unhappiness	censure severely or angrily
express one's opinion openly and without fear or hesitation	show one's unhappiness or critical attitude
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