grouse vs wildfowl

grouse and wildfowl both are nouns.

Word	Noun	Adjective	Verb	Adverb
grouse	Yes	No	Yes	No
wildfowl	Yes	No	No	No

As nouns, wildfowl is a hypernym of grouse; that is, wildfowl is a word with a broader meaning than grouse:

grouse: flesh of any of various grouse of the family Tetraonidae; usually roasted; flesh too dry to broil
wildfowl: flesh of any of a number of wild game birds suitable for food

grouse (noun)	wildfowl (noun)
popular game bird having a plump body and feathered legs and feet	flesh of any of a number of wild game birds suitable for food
flesh of any of various grouse of the family Tetraonidae; usually roasted; flesh too dry to broil

grouse (verb)	wildfowl (verb)
complain
hunt grouse