class Aves vs order Caprimulgiformes

class Aves and order Caprimulgiformes both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Aves	Yes	No	No	No
order Caprimulgiformes	Yes	No	No	No

class Aves (noun)	order Caprimulgiformes (noun)
(ornithology) the class of birds	goatsuckers, frogmouths, oilbirds