ex·​trem·​o·​phile ik-ˈstrē-mə-ˌfī(-ə)l How to pronounce extremophile (audio)
: an organism that lives under extreme environmental conditions (as in a hot spring or ice cap)

Did you know?

No, an extremophile is not an enthusiast of extreme sports (though -phile does mean "one who loves or has an affinity for"). Rather, extremophiles are organisms—mostly microorganisms—that thrive in environments once considered uninhabitable, from places with high levels of toxicity and radiation to boiling-hot deep-sea volcanoes to Antarctic ice sheets. Scientists have even created a new biological domain to classify some of these extremophiles: Archaea (from Greek archaios, meaning "ancient"). These extremophiles may have a lot in common with the first organisms to appear on earth billions of years ago. If so, they can give us insight into how life on our planet may have arisen. They are also being studied to learn about possible life forms on other planets, where conditions are extreme compared to conditions on Earth.

Examples of extremophile in a Sentence

Recent Examples on the Web And where there’s water and warmth, there will be extremophiles—tough little creatures that can thrive in desolate wastelands and temperatures that dip below zero. IEEE Spectrum, 31 Jan. 2011 Water bears aren’t actually extremophiles, more extremo-tolerant. Katie Liu, Discover Magazine, 14 Dec. 2023 Exhilarating detections of the first exoplanets in the 1990s, alongside a growing understanding of microbiology and extremophiles, had generated scientific buzz. Katie Liu, Discover Magazine, 25 Oct. 2023 But nothing else matches the extremophiles, animals like the dinosaur shrimp and fairy shrimp, that can lay dormant for decades. Caroline Delbert, Popular Mechanics, 7 Sep. 2023 Even some Earth-dwelling extremophiles—organisms that live in exceptionally harsh conditions—are poorly understood. Margaret Osborne, Smithsonian Magazine, 27 July 2023 Psammophiles themselves are examples of extremophiles, organisms that love extreme environments. Frances Vinall, Washington Post, 2 June 2023 Chemical interactions or geologic activity could provide energy for these life-forms, much as deep-sea volcanic vents like those German has discovered provide energy for extremophiles on Earth. Rebecca Boyle, Scientific American, 18 Apr. 2023 Some organisms—extremophiles—have adapted to live life in these severe environments. Jennifer Leman, Popular Mechanics, 15 Apr. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'extremophile.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1989, in the meaning defined above

Time Traveler
The first known use of extremophile was in 1989


Dictionary Entries Near extremophile

Cite this Entry

“Extremophile.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/extremophile. Accessed 19 Apr. 2024.

Last Updated: - Updated example sentences
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