killifish
nounAny of numerous small fishes of the family Fundulidae and related families of the order Cyprinidontiformes, chiefly inhabiting fresh and brackish waters in warm regions and popular in home aquariums.
nounA name given about New York to fishes of the family Cyprinodontidæ and genera Fundulus and Hydrargyra, having an elongated form, depressed scaly head, bands of pointed teeth in the jaws, and a dorsal fin mostly in advance of the anal, with from 11 to 17 rays.
nounAny one of several small American cyprinodont fishes of the genus Fundulus and allied genera. They live equally well in fresh and brackish water, or even in the sea. They are usually striped or barred with black. Called also
Any of a number of tiny fish in the
small mostly marine warm-water carp-like schooling fishes; used as bait or aquarium fishes or in mosquito control