genus Elanus vs bird genus

genus Elanus and bird genus both are nouns.

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

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

genus Elanus (noun)	bird genus (noun)
a genus of small kites of both Old and New Worlds	a genus of birds