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)
Recent Examples of killifish from the Web
No new species of non-native fish were turned in, but some unusual catches included pacu, pike killifish and brown hoplo.
The fish there survive levels of pollution up to 8,000 times the lethal dose for most killifish.
The researchers sequenced the entire genomes of these fish and compared them to the genomes of killifish in unpolluted waters nearby each site.
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Origin and Etymology of killifish
killie killifish (perhaps from 3kill) + fish
First Known Use: 1836See Words from the same year
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