killifish

American  

[kil-ee-fish] / ˈkɪl iˌfɪʃ /

noun

killifish, plural killifishes plural

1. any of several small, oviparous cyprinodont fishes, especially of the genus Fundulus, found in salt, brackish, and fresh waters.

2. any of several livebearers.

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killifish British  

/ ˈkɪlɪˌfɪʃ /

noun

1. any of various chiefly American minnow-like cyprinodont fishes of the genus Fundulus and related genera, of fresh and brackish waters: used as aquarium fishes, to control mosquitoes, and as anglers' bait

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Other Word Forms

Noun Inflected Forms

• killifish
  plural
• killifishes
  plural

Etymology

Origin of killifish

1805–15, perhaps kill ² + -i- (unexplained) + fish

Example Sentences

See Examples For:

killifish killifishes

To investigate what happens in aging brains, the researchers turned to the turquoise killifish, Nothobranchius furzeri.

From Science Daily ● May 29, 2026

The new findings show that similar aging mechanisms also occur in more complex vertebrates like killifish and humans.

From Science Daily ● May 29, 2026

The killifish results provide a behavioral perspective on this phenomenon.

From Science Daily ● Mar. 26, 2026

"Seeing these effects emerge so clearly in a rapid-aging model like our killifish was striking," Paulmann said.

From Science Daily ● Jan. 30, 2026

The plains killifish was collected by me only at Station 42-S.

From Fishes of the Big Blue River Basin, Kansas by Minckley, W. L.

In addition, there are small killifishes whose closest relatives are found in the Seychelles, and freshwater toadfishes with affinities to species in India.

From New York Times ● Jun. 13, 2011