leatherfish vs leatherjacket

leatherfish and leatherjacket both are nouns.

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

As nouns, leatherfish and leatherjacket are synonyms defined as:

leatherfish and leatherjacket: any of several brightly colored tropical filefishes

leatherfish (noun)	leatherjacket (noun)
any of several brightly colored tropical filefishes	any of several brightly colored tropical filefishes
	any of several New World tropical fishes having tiny embedded scales
	tough-skinned larva of certain crane flies