killifish Meaning, Definition & Usage

  1. noun small mostly marine warm-water carp-like schooling fishes; used as bait or aquarium fishes or in mosquito control

WordNet

Kil"li*fish` noun
Definitions
  1. (Zoöl.) Any 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 minnow, and brook fish. See Minnow.

Webster 1913