ocean perch vs rockfish

ocean perch and rockfish both are nouns.

Word	Noun	Adjective	Verb	Adverb
ocean perch	Yes	No	No	No
rockfish	Yes	No	No	No

As nouns, rockfish is a hypernym of ocean perch; that is, rockfish is a word with a broader meaning than ocean perch:

ocean perch: large fish of northern Atlantic coasts of America and Europe
rockfish: marine food fish found among rocks along the northern coasts of Europe and America

As nouns, rockfish is a hypernym of ocean perch; that is, rockfish is a word with a broader meaning than ocean perch:

ocean perch: North Atlantic rockfish
rockfish: the lean flesh of any of various valuable market fish caught among rocks

ocean perch (noun)	rockfish (noun)
large fish of northern Atlantic coasts of America and Europe	marine food fish found among rocks along the northern coasts of Europe and America
North Atlantic rockfish	marine food and game fish with dark longitudinal stripes; migrates upriver to spawn; sometimes placed in the genus Morone
	the lean flesh of any of various valuable market fish caught among rocks