class Reptilia vs subclass Anapsida

class Reptilia and subclass Anapsida both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Reptilia	Yes	No	No	No
subclass Anapsida	Yes	No	No	No

class Reptilia (noun)	subclass Anapsida (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	oldest known reptiles; turtles and extinct Permian forms