lookdown fish vs dollarfish

lookdown fish and dollarfish both are nouns.

Word	Noun	Adjective	Verb	Adverb
lookdown fish	Yes	No	No	No
dollarfish	Yes	No	No	No

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

lookdown fish: similar to moonfish but with eyes high on the truncated forehead
dollarfish: any of several silvery marine fishes with very flat bodies

Other hypernyms of lookdown fish include Atlantic moonfish, horse-head, horsefish, horsehead, moonfish, Selene setapinnis.

lookdown fish (noun)	dollarfish (noun)
similar to moonfish but with eyes high on the truncated forehead	small food fish of Atlantic coast
	any of several silvery marine fishes with very flat bodies