ex·​tra·​ter·​res·​tri·​al | \ˌek-strə-tə-ˈre-strē-əl, -ˈres-chəl, -ˈresh-chəl\

Definition of extraterrestrial 

(Entry 1 of 2)

: originating, existing, or occurring outside the earth or its atmosphere extraterrestrial life



Definition of extraterrestrial (Entry 2 of 2)

: a being from another world : an extraterrestrial being

Examples of extraterrestrial in a Sentence

Recent Examples on the Web: Adjective

And while the debate over whether extraterrestrials exist IRL is still up for debate, hearing your fave celebs recount their alien adventures and extraterrestrial encounters is probably the greatest thing EVER. Seventeen.com Editors, Seventeen, "10 Celebs Who Totally Believe in Aliens," 20 Oct. 2015 By latest count, Jupiter is home to more moons than any other planet in the solar system, ranging from the largest, Ganymede, which is two-thirds the size of Mars, to the most promising candidate for extraterrestrial life, Europa. Robert Lee Hotz, WSJ, "The Hunt for ‘Planet Nine’ Unearths 12 New Moons Around Jupiter," 17 July 2018 Sadly, extraterrestrial life in our solar system could very likely be something way more primitive. Jacek Krywko, Ars Technica, "To make Curiosity (et al) more curious, NASA and ESA smarten up AI in space," 16 July 2018 The SETI Institute is perhaps best known for its ongoing search for extraterrestrial intelligence, but its podcast, which is partially funded by the NASA Astrobiology Institute, isn’t all aliens and speculation. Erin Blakemore, Washington Post, "Selling science, and debunking pseudoscience, through great stories," 23 June 2018 Broder finds the surreal in the carnal (in this way, her book reminds me a bit of Miranda July’s The First Bad Man) and the mundane in the extraterrestrial. Julia Felsenthal, Vogue, "In Melissa Broder’s The Pisces, a Darkly Erotic Love Story Between a Woman and a Merman," 1 May 2018 Mars has long been everyone's hands-down favorite in the search for extraterrestrial life. NBC News, "Here's the scientific explanation for that 'alien spaceship' on Mars," 23 June 2018 Although not exactly the lawless wild west, the search for extraterrestrial life remains so speculative that meaningful regulations are few and far between. Leonard David, Scientific American, "As Space Becomes a Busy Place, NASA Bolsters Its Planet-Contamination Police," 3 July 2018 Professor Lattanzio reported on work done by an international team of researchers who have come up with a set of specific predictions about the nature of extraterrestrial life if it is discovered on Enceladus, Europa or beyond. Jamie Seidel, Fox News, "Wild new alien theory emerges," 28 June 2018

Recent Examples on the Web: Noun

Here are oceans of contingencies navigable only by an alternative race of extraterrestrials: the angels of heaven. Brad Leithauser, WSJ, "‘The Grandmaster’ Review: The 64-Square Universe," 8 Nov. 2018 Maybe extraterrestrials will be able to figure this out after all. Cory Zapatka, The Verge, "Decoding images from the Golden Record," 30 Oct. 2018 Elle Fanning plays one of the extraterrestrials, who find themselves in the suburbs of London in 1977. Gabe Cohn, New York Times, "What’s on TV Saturday: ‘American Made’ and ‘I Want That Wedding’," 9 June 2018 Bettina Rodriguez Aguilera, a former city councilwoman from the west Dade suburb of Doral, has publicly discussed meeting extraterrestrials as a child. David Smiley And Alex Daugherty, miamiherald, "They've met aliens and dictators and slimed Al Gore: Meet Ros-Lehtinen's would-be heirs | Miami Herald," 23 May 2018 Alex Sharp leads the cast, which includes Nicole Kidman (as a human) and Elle Fanning and Ruth Wilson (as extraterrestrials). Ben Kenigsberg, New York Times, "Summer 2018 Movie Release Schedule," 4 May 2018 So how close are the nearest signaling extraterrestrials? NBC News, "Simple math shows how many space aliens may be out there," 26 Jan. 2018 In Space Opera, humanity is living blissfully unaware of alien life, until extraterrestrials appear and invite them into an advanced intergalactic civilization. Andrew Liptak, The Verge, "Space Opera is the funniest science fiction novel I’ve read since Hitchhiker’s Guide to the Galaxy," 14 Apr. 2018 Would Boyajian have really raised so much money if KIC 8462852 hadn’t generated so much hype about intelligent extraterrestrials? Neel V. Patel, Slate Magazine, "How Interesting Does Science Have to Be for the Public to Fund It?," 4 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'extraterrestrial.' 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 extraterrestrial


1848, in the meaning defined above


1950, in the meaning defined above

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Last Updated

7 Dec 2018

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The first known use of extraterrestrial was in 1848

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English Language Learners Definition of extraterrestrial

: coming from or existing outside the planet Earth

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Spanish Central: Translation of extraterrestrial

Nglish: Translation of extraterrestrial for Spanish Speakers

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