kil·​li·​fish | \ ˈki-li-ˌfish How to pronounce killifish (audio) \

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)

Examples of killifish in a Sentence

Recent Examples on the Web

Snowy egrets stalked the shallows, stabbing menhaden and killifish and the occasional shrimp swept along in the current. Shannon Tompkins, Houston Chronicle, "Bay food chain comes to life with tide change," 14 Apr. 2018 Meanwhile, golden topminnows and killifish shelter in the shadows hoping to avoid bass and bream lurking in the underwater forest created by the tall stalks and flower stems. Ben Raines |,, "Stranded in the Delta with nothing but time and a camera," 30 Aug. 2017 No new species of non-native fish were turned in, but some unusual catches included pacu, pike killifish and brown hoplo. Jan Engoren,, "Anglers catch 2,200 non-native fish in Everglades roundup," 10 May 2017 The researchers sequenced the entire genomes of these fish and compared them to the genomes of killifish in unpolluted waters nearby each site. National Geographic, "These Fish Evolved to Live in Extremely Toxic Water," 8 Dec. 2016 The fish there survive levels of pollution up to 8,000 times the lethal dose for most killifish. National Geographic, "These Fish Evolved to Live in Extremely Toxic Water," 8 Dec. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'killifish.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of killifish

1836, in the meaning defined at sense 1

History and Etymology for killifish

killie killifish (perhaps from kill entry 3) + fish

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The first known use of killifish was in 1836

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What made you want to look up killifish? Please tell us where you read or heard it (including the quote, if possible).


an act or instance of returning to life

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