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 Take the trematode preying on the California killifish, a normally secretive bait fish that hangs out in western salt marshes. Washington Post, "Parasites may not be cute and cuddly, but they need saving too, scientists say," 14 Dec. 2020 And several studies published in the past 3 years suggest the eyes of killifish and water fleas vary in size depending on the presence of predators. Elizabeth Pennisi, Science | AAAS, "Eye size predicts where birds breed and feed," 27 Oct. 2020 But a 2019 study found that the intrepid eggs of the killifish, which can enter a kind of hibernation to survive dry spells buried in sand and soil, were able to survive a trip through both ends of a swan. Alex Fox, Smithsonian Magazine, "Fish Eggs Can Survive a Journey Through Both Ends of a Duck," 2 July 2020 This video compares the embryos and life spans of killifish who either experienced or skipped diapause, capturing time-lapses and detailed snapshots of their embryonic development. Joel Goldberg, Science | AAAS, "Watch African killifish embryos enter suspended animation to survive," 20 Feb. 2020 For about 5 to 6 months, this killifish, roughly the size of a thumb, puts most of its embryo’s critical body processes—including muscle and nerve cell growth—on hold. Joel Goldberg, Science | AAAS, "Watch African killifish embryos enter suspended animation to survive," 20 Feb. 2020 The smaller reds readily take live shrimp and killifish minnows, while the lunkers prefer finger mullet, grunts and pinfish. Frank Sargeant, al, "Friday Fishing Report: What’s hooking fish on Alabama lakes?," 1 Nov. 2019 Baitfish traps are easy to use, and are very effective at collecting some small baitfish, including pinfish, killifish, and mud or bull minnows. Bob Mcnally, Field & Stream, "The Ultimate Guide to Catching and Keeping Saltwater Live Bait," 2 Jan. 2020 Live mullet or killifish are by far the best bait but a jig tipped with shrimp and worked slowly along bottom also catches some of these tasty flatfish. Frank Sargeant, al, "Friday Fishing Report: Big catfish hooked on Tennessee Valley lakes," 15 Nov. 2019

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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Cite this Entry

“Killifish.” Dictionary, Merriam-Webster, Accessed 15 May. 2021.

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