stromateid fish vs percoidean

stromateid fish and percoidean both are nouns.

Word	Noun	Adjective	Verb	Adverb
stromateid fish	Yes	No	No	No
percoidean	Yes	No	No	No

As nouns, percoidean is a hypernym of stromateid fish; that is, percoidean is a word with a broader meaning than stromateid fish:

stromateid fish: small marine fish with a short compressed body and feeble spines
percoidean: any of numerous spiny-finned fishes of the order Perciformes

Other hypernyms of stromateid fish include percoid, percoid fish.

stromateid fish (noun)	percoidean (noun)
small marine fish with a short compressed body and feeble spines	any of numerous spiny-finned fishes of the order Perciformes