lament vs sound off

lament is a noun but sound off is not a noun.

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

As verbs, sound off is a hypernym of lament; that is, sound off is a word with a broader meaning than lament:

Other hypernyms of lament include complain, kick, kvetch, plain, quetch.

lament (noun)	sound off (noun)
a mournful poem; a lament for the dead
a song or hymn of mourning composed or performed as a memorial to a dead person
a cry of sorrow and grief

lament (verb)	sound off (verb)
regret strongly	express complaints, discontent, displeasure, or unhappiness
express grief verbally	express one's opinion openly and without fear or hesitation
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