chaetodon vs butterfly fish

chaetodon and butterfly fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
chaetodon	Yes	No	No	No
butterfly fish	Yes	No	No	No

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

chaetodon: any fish of the genus Chaetodon
butterfly fish: small usually brilliantly colored tropical marine fishes having narrow deep bodies with large broad fins; found worldwide

chaetodon (noun)	butterfly fish (noun)
any fish of the genus Chaetodon	small usually brilliantly colored tropical marine fishes having narrow deep bodies with large broad fins; found worldwide