genus Picumnus vs bird genus

genus Picumnus and bird genus both are nouns.

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

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

genus Picumnus (noun)	bird genus (noun)
a genus of Picidae containing the piculets (Picumnus)	a genus of birds