scorpionfish vs sea scorpion

scorpionfish and sea scorpion both are nouns.

Word	Noun	Adjective	Verb	Adverb
scorpionfish	Yes	No	No	No
sea scorpion	Yes	No	No	No

As nouns, scorpionfish and sea scorpion are synonyms defined as:

scorpionfish and sea scorpion: marine fishes having a tapering body with an armored head and venomous spines

Other synonyms of scorpionfish include scorpion fish.

scorpionfish (noun)	sea scorpion (noun)
marine fishes having a tapering body with an armored head and venomous spines	marine fishes having a tapering body with an armored head and venomous spines