Anura vs class Amphibia

Anura and class Amphibia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Anura	Yes	No	No	No
class Amphibia	Yes	No	No	No

Anura (noun)	class Amphibia (noun)
frogs, toads, tree toads	the class of vertebrates that live on land but breed in water, frogs, toads, newts, salamanders, caecilians