cornetfish vs teleost fish

cornetfish and teleost fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
cornetfish	Yes	No	No	No
teleost fish	Yes	No	No	No

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

cornetfish: slender tropical fish with a long tubular snout and bony plates instead of scales
teleost fish: a bony fish of the subclass Teleostei

Other hypernyms of cornetfish include teleost, teleostan.

cornetfish (noun)	teleost fish (noun)
slender tropical fish with a long tubular snout and bony plates instead of scales	a bony fish of the subclass Teleostei