sand stargazer vs percoid

sand stargazer and percoid both are nouns.

Word	Noun	Adjective	Verb	Adverb
sand stargazer	Yes	No	No	No
percoid	Yes	No	No	No

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

sand stargazer: small pallid fishes of shoal tropical waters of North America and South America having eyes on stalks atop head; they burrow in sand to await prey
percoid: any of numerous spiny-finned fishes of the order Perciformes

Other hypernyms of sand stargazer include percoid fish, percoidean.

sand stargazer (noun)	percoid (noun)
small pallid fishes of shoal tropical waters of North America and South America having eyes on stalks atop head; they burrow in sand to await prey	any of numerous spiny-finned fishes of the order Perciformes