killifish

American

[kil-ee-fish] / ˈkɪl iˌfɪʃ /

noun

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

killifish British

/ ˈkɪlɪˌfɪʃ /

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of killifish

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

killifish killifishes

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

From Science Daily ● May 29, 2026

To do this, they used the African turquoise killifish, a species with a lifespan of just four to eight months.

From Science Daily ● Mar. 26, 2026

The African turquoise killifish is among the fastest-aging vertebrates known, living only four to six months.

From Science Daily ● Jan. 30, 2026

It is also an important global center of seasonal killifish diversity.

From Science Daily ● Dec. 25, 2025

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

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023