helleri vs topminnow

helleri and topminnow both are nouns.

Word	Noun	Adjective	Verb	Adverb
helleri	Yes	No	No	No
topminnow	Yes	No	No	No

As nouns, helleri and topminnow are synonyms defined as:

helleri and topminnow: freshwater fish of Central America having a long swordlike tail; popular aquarium fish

Other synonyms of helleri include swordtail, Xyphophorus helleri.

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