topminnow vs cypriniform fish

topminnow and cypriniform fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
topminnow	Yes	No	No	No
cypriniform fish	Yes	No	No	No

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

topminnow: small usually brightly-colored viviparous surface-feeding fishes of fresh or brackish warm waters; often used in mosquito control
cypriniform fish: a soft-finned fish of the order Cypriniformes

topminnow (noun)	cypriniform fish (noun)
small usually brightly-colored viviparous surface-feeding fishes of fresh or brackish warm waters; often used in mosquito control	a soft-finned fish of the order Cypriniformes
freshwater fish of Central America having a long swordlike tail; popular aquarium fish