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

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

From Science Daily ● Jan. 30, 2026

A new study published in Kidney International reports that a class of medications called SGLT2 inhibitors helped prevent age-related damage to kidney structure and function in the African turquoise killifish.

From Science Daily ● Jan. 30, 2026

Scientists have confirmed the rediscovery of Moema claudiae, a rare seasonal killifish species in Bolivia that had been considered possibly extinct.

From Science Daily ● Dec. 25, 2025

To overcome this, the Exeter team developed a new infection model using Arabian killifish.

From Science Daily ● Dec. 23, 2025

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

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

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