leatherjacket vs filefish

leatherjacket and filefish both are nouns.

Word	Noun	Adjective	Verb	Adverb
leatherjacket	Yes	No	No	No
filefish	Yes	No	No	No

As nouns, filefish is a hypernym of leatherjacket; that is, filefish is a word with a broader meaning than leatherjacket:

leatherjacket: any of several brightly colored tropical filefishes
filefish: narrow flattened warm-water fishes with leathery skin and a long file-like dorsal spine

leatherjacket (noun)	filefish (noun)
any of several brightly colored tropical filefishes	narrow flattened warm-water fishes with leathery skin and a long file-like dorsal spine
any of several New World tropical fishes having tiny embedded scales
tough-skinned larva of certain crane flies