molly vs live-bearer

molly and live-bearer both are nouns.

Word	Noun	Adjective	Verb	Adverb
molly	Yes	No	No	No
live-bearer	Yes	No	No	No

As nouns, live-bearer is a hypernym of molly; that is, live-bearer is a word with a broader meaning than molly:

molly: popular aquarium fish
live-bearer: small usually brightly-colored viviparous surface-feeding fishes of fresh or brackish warm waters; often used in mosquito control

Other hypernyms of molly include poeciliid, poeciliid fish, topminnow.

molly (noun)	live-bearer (noun)
popular aquarium fish	small usually brightly-colored viviparous surface-feeding fishes of fresh or brackish warm waters; often used in mosquito control