order Lepidoptera vs class Insecta

order Lepidoptera and class Insecta both are nouns.

Word	Noun	Adjective	Verb	Adverb
order Lepidoptera	Yes	No	No	No
class Insecta	Yes	No	No	No

order Lepidoptera (noun)	class Insecta (noun)
moths and butterflies	insects; about five-sixths of all known animal species