order Acarina vs class Arachnida

order Acarina and class Arachnida both are nouns.

Word	Noun	Adjective	Verb	Adverb
order Acarina	Yes	No	No	No
class Arachnida	Yes	No	No	No

order Acarina (noun)	class Arachnida (noun)
mites and ticks	a large class of arthropods including spiders and ticks and scorpions and daddy longlegs; have four pairs of walking legs and no wings