Dromaius vs bird genus

Dromaius and bird genus both are nouns.

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

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

Dromaius (noun)	bird genus (noun)
a genus of birds in the order Casuariiformes	a genus of birds