Definition of killifish
1 : any of a family (Cyprinodontidae) of numerous small oviparous fishes much used as bait and in mosquito control
2 : any of various live-bearers (family Poeciliidae)
Origin of killifish
killie killifish (perhaps from 3kill) + fish
First Known Use: 1836
Learn More about killifish
Britannica.com: Encyclopedia article about "killifish"
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