spadefish vs percoid fish

spadefish and percoid fish both are nouns.

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

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

spadefish: deep-bodied disk-shaped food fish of warmer western Atlantic coastal waters
percoid fish: any of numerous spiny-finned fishes of the order Perciformes

Other hypernyms of spadefish include percoid, percoidean.

spadefish (noun)	percoid fish (noun)
deep-bodied disk-shaped food fish of warmer western Atlantic coastal waters	any of numerous spiny-finned fishes of the order Perciformes