order Ciconiiformes vs class Aves

order Ciconiiformes and class Aves both are nouns.

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

order Ciconiiformes (noun)	class Aves (noun)
order of chiefly tropical marsh-dwelling fish-eating wading birds with long legs and bills and (except for flamingos) unwebbed feet: herons, storks, spoonbills, flamingos, ibises	(ornithology) the class of birds