genus Cacatua vs bird genus

genus Cacatua and bird genus both are nouns.

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

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

genus Cacatua: a genus of Psittacidae containing the cockatoos, found from the Philippines and Wallacea east to the Solomon Islands and south to Australia (Kakatoe, Cacatua)
bird genus: a genus of birds

genus Cacatua (noun)	bird genus (noun)
a genus of Psittacidae containing the cockatoos, found from the Philippines and Wallacea east to the Solomon Islands and south to Australia (Kakatoe, Cacatua)	a genus of birds