seasnail vs scorpaenoid fish

seasnail and scorpaenoid fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
seasnail	Yes	No	No	No
scorpaenoid fish	Yes	No	No	No

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

seasnail: small tadpole-shaped cold-water fishes with pelvic fins forming a sucker; related to lumpfish
scorpaenoid fish: fishes having the head armored with bony plates

Other hypernyms of seasnail include scorpaenoid.

seasnail (noun)	scorpaenoid fish (noun)
small tadpole-shaped cold-water fishes with pelvic fins forming a sucker; related to lumpfish	fishes having the head armored with bony plates
any of several creeping marine gastropods with a spirally coiled shell: whelks, tritons, moon shells, neritids