class Hexapoda vs order Odonata

class Hexapoda and order Odonata both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Hexapoda	Yes	No	No	No
order Odonata	Yes	No	No	No

class Hexapoda (noun)	order Odonata (noun)
insects; about five-sixths of all known animal species	dragonflies and damselflies