ex·​trem·​o·​phile | \ ik-ˈstrē-mə-ˌfī(-ə)l How to pronounce extremophile (audio) \

Definition of extremophile

: an organism that lives under extreme environmental conditions (as in a hot spring or ice cap)

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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 microbes 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 microbes: 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 Orphan’s work with extremophiles — organisms that survive under extreme conditions like high pressure or a complete lack of sunlight — could shed light on the origins of life on Earth and the potential for life on other worlds, among other things. Los Angeles Times, 29 Apr. 2020 Some organisms—extremophiles—have adapted to live life in these severe environments. Jennifer Leman, Popular Mechanics, 29 Dec. 2019 One major factor that many extremophiles share is their ability to tolerate or even feed off of methane instead of oxygen or carbon dioxide, like methanotrophs, which are bacteria that eat methane and release oxygen as a byproduct. Caroline Delbert, Popular Mechanics, 21 Nov. 2019 The overall family of extremophiles that live on or despite radiation includes both fungi and bacteria, and different species have different mechanisms for absorbing or tolerating radiation. Caroline Delbert, Popular Mechanics, 6 Feb. 2020 These extremophiles can also be found in highly salty or highly acidic environments. Robin George Andrews, New York Times, 1 Nov. 2019 But one of the new nematodes from the genus Auanema did reproduce in the lab, which will provide researchers a new model extremophile to work with. Jason Daley, Smithsonian, 1 Oct. 2019 The star ingredients in Nature in a Jar, which is billed specifically to address fatigued, sensitive and dry skin, are extremophile desert plants (aka succulents), including agave, jojoba, cactus, and prickly pear oil. Rebecca Dancer, Allure, 13 Dec. 2019 For instance, Kaltenegger’s group has studied the spectra of 137 microorganisms, including extremophiles that thrive in Earth's most inhospitable environs. Sarah Lewin Frasier, Scientific American, 12 May 2015

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'extremophile.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of extremophile

1989, in the meaning defined above

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The first known use of extremophile was in 1989

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Cite this Entry

“Extremophile.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/extremophile. Accessed 14 Jun. 2021.

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