worm fish vs percoidean

worm fish and percoidean both are nouns.

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

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

worm fish: poorly known family of small tropical shallow-water fishes related to gobies
percoidean: any of numerous spiny-finned fishes of the order Perciformes

Other hypernyms of worm fish include percoid, percoid fish.

worm fish (noun)	percoidean (noun)
poorly known family of small tropical shallow-water fishes related to gobies	any of numerous spiny-finned fishes of the order Perciformes