Amphipoda vs animal order

Amphipoda and animal order both are nouns.

Word	Noun	Adjective	Verb	Adverb
Amphipoda	Yes	No	No	No
animal order	Yes	No	No	No

As nouns, animal order is a hypernym of Amphipoda; that is, animal order is a word with a broader meaning than Amphipoda:

Amphipoda: small flat-bodied semiterrestrial crustaceans: whale lice, sand-hoppers, skeleton shrimp
animal order: the order of animals

Amphipoda (noun)	animal order (noun)
small flat-bodied semiterrestrial crustaceans: whale lice, sand-hoppers, skeleton shrimp	the order of animals