bird genus vs genus

bird genus and genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
bird genus	Yes	No	No	No
genus	Yes	No	No	No

As nouns, genus is a hypernym of bird genus; that is, genus is a word with a broader meaning than bird genus:

bird genus (noun)	genus (noun)
a genus of birds	a general kind of something
	(biology) taxonomic group containing one or more species