class Reptilia vs subphylum Craniata

class Reptilia and subphylum Craniata both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Reptilia	Yes	No	No	No
subphylum Craniata	Yes	No	No	No

class Reptilia (noun)	subphylum Craniata (noun)
class of cold-blooded air-breathing vertebrates with completely ossified skeleton and a body usually covered with scales or horny plates; once the dominant land animals	fishes, amphibians, reptiles, birds, mammals