genus Elephas vs mammal genus

genus Elephas and mammal genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Elephas	Yes	No	No	No
mammal genus	Yes	No	No	No

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

genus Elephas (noun)	mammal genus (noun)
type genus of the family Elephantidae	a genus of mammals