grouse vs sound off

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

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

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

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

grouse (noun)	sound off (noun)
popular game bird having a plump body and feathered legs and feet
flesh of any of various grouse of the family Tetraonidae; usually roasted; flesh too dry to broil

grouse (verb)	sound off (verb)
complain	express complaints, discontent, displeasure, or unhappiness
hunt grouse	express one's opinion openly and without fear or hesitation
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