reptile genus vs genus

reptile genus and genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
reptile genus	Yes	No	No	No
genus	Yes	No	No	No

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

reptile genus (noun)	genus (noun)
a genus of reptiles	a general kind of something
	(biology) taxonomic group containing one or more species