killifish
noun
kil·li·fish
ˈki-li-ˌfish 
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
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Evolutionary rescue has been demonstrated in lab settings but researchers only had partial observations of it in the wild before: in cancer resistance in Tasmanian devils and adaptation to pollution in killifish.
—
Jacopo Prisco, CNN Money, 12 Mar. 2026
For the first time in 10 years, researchers have discovered a new species of Xenurolebias killifish from an isolated swamp about 2 feet deep in eastern Brazil.
—Lauren Liebhaber
september 23, Miami Herald, 23 Sep. 2025
Most species are holding fewer cards than the killifish.
—Brian Owens, Smithsonian Magazine, 26 Jan. 2024
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Jacopo Prisco, CNN Money, 12 Mar. 2026
For the first time in 10 years, researchers have discovered a new species of Xenurolebias killifish from an isolated swamp about 2 feet deep in eastern Brazil.
—Lauren Liebhaber
september 23, Miami Herald, 23 Sep. 2025
Most species are holding fewer cards than the killifish.
—Brian Owens, Smithsonian Magazine, 26 Jan. 2024
See All Example Sentences for killifish
Cite this Entry
“Killifish.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/killifish. Accessed 30 Mar. 2026.
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