percoid fish vs Percomorphi

percoid fish and Percomorphi both are nouns.

Word	Noun	Adjective	Verb	Adverb
percoid fish	Yes	No	No	No
Percomorphi	Yes	No	No	No

percoid fish (noun)	Percomorphi (noun)
any of numerous spiny-finned fishes of the order Perciformes	one of the largest natural groups of fishes of both marine and fresh water: true perches, basses, tuna