scorpionfish vs scorpaenid fish

scorpionfish and scorpaenid fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
scorpionfish	Yes	No	No	No
scorpaenid fish	Yes	No	No	No

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

scorpionfish: marine fishes having a tapering body with an armored head and venomous spines
scorpaenid fish: any of numerous carnivorous usually bottom-dwelling warm-water marine fishes found worldwide but most abundant in the Pacific

Other hypernyms of scorpionfish include scorpaenid.

scorpionfish (noun)	scorpaenid fish (noun)
marine fishes having a tapering body with an armored head and venomous spines	any of numerous carnivorous usually bottom-dwelling warm-water marine fishes found worldwide but most abundant in the Pacific