Source : WordNet®

topminnow
     n 1: small usually brightly-colored viviparous surface-feeding
          fishes of fresh or brackish warm waters; often used in
          mosquito control [syn: {poeciliid fish}, {poeciliid}, {live-bearer}]
     2: freshwater fish of Central America having a long swordlike
        tail; popular aquarium fish [syn: {swordtail}, {helleri},
        {Xyphophorus helleri}]