bigeye vs percoid

bigeye and percoid both are nouns.

Word	Noun	Adjective	Verb	Adverb
bigeye	Yes	No	No	No
percoid	Yes	No	No	No

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

bigeye: red fishes of American coastal tropical waters having very large eyes and rough scales
percoid: any of numerous spiny-finned fishes of the order Perciformes

Other hypernyms of bigeye include percoid fish, percoidean.

bigeye (noun)	percoid (noun)
red fishes of American coastal tropical waters having very large eyes and rough scales	any of numerous spiny-finned fishes of the order Perciformes