com·​et | \ ˈkä-mət How to pronounce comet (audio) \

Definition of comet

: a celestial body that appears as a fuzzy head usually surrounding a bright nucleus, that has a usually highly eccentric orbit, that consists primarily of ice and dust, and that often develops one or more long tails when near the sun

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Other Words from comet

cometary \ ˈkä-​mə-​ˌter-​ē How to pronounce cometary (audio) \ adjective
cometic \ kə-​ˈme-​tik How to pronounce cometic (audio) , kä-​ \ adjective

Examples of comet in a Sentence

Recent Examples on the Web The Earth will pass through bits of the comet’s debris — which show up as meteors, or shooting stars, in the sky — best seen late Tuesday/early Wednesday morning. Los Angeles Times, "Orionid meteor showers peak tonight. Here’s where to watch," 20 Oct. 2020 Fisher says the 2-foot-wide capsule is protected with the same sort of heat shield that safely returned samples from NASA’s Stardust mission through the tail of a comet. Daniel Oberhaus, Wired, "NASA’s OSIRIS-REx Is About to Touch an Asteroid," 19 Oct. 2020 However the future unfolds, it’s not something to be predicted, like the passage of a comet. Robert Kunzig, National Geographic, "Let’s not waste this crucial moment: We need to stop abusing the planet," 13 Oct. 2020 Like the 2010 Auburn Tigers, the 2019 LSU Tigers were like a comet streaking through the sky. Dan Wolken, USA TODAY, "Opinion: Shocking transformation for defending national champ LSU makes fans wonder how bad it will get," 12 Oct. 2020 The Perseids, which occur every mid-summer, are caused by the debris left behind by the Swift-Tuttle comet, which orbits the solar system once every 133 years. Steve Rubenstein,, "Here’s how to view the Perseid meteor shower in the Bay Area," 8 Aug. 2020 Earth passes close to the orbit of this comet around October 8 each year. Ashley Strickland, CNN, "Draconid meteor shower 2020: How and when to watch," 6 Oct. 2020 Back in March, the Neowise space telescope discovered a new comet. Kelly Allen, House Beautiful, "These Are the Best Photos of This Year's Newly-Discovered Comet," 22 July 2020 Between a once-in-a-lifetime comet and a near-miss with an extremely close asteroid, 2020 has been a strange year for outer space. Sophie Lewis, CBS News, "A rare "blue moon" will light up the Halloween night sky," 22 Sep. 2020

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

before the 12th century, in the meaning defined above

History and Etymology for comet

Middle English comete, from Old English cometa, from Latin, from Greek komētēs, literally, long-haired, from koman to wear long hair, from komē hair

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Time Traveler for comet

Time Traveler

The first known use of comet was before the 12th century

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Statistics for comet

Last Updated

25 Oct 2020

Cite this Entry

“Comet.” Dictionary, Merriam-Webster, Accessed 31 Oct. 2020.

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More Definitions for comet


How to pronounce comet (audio)

English Language Learners Definition of comet

: an object in outer space that develops a long, bright tail when it passes near the sun


com·​et | \ ˈkä-mət How to pronounce comet (audio) \

Kids Definition of comet

: a small bright heavenly body that develops a cloudy tail as it moves in an orbit around the sun

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More from Merriam-Webster on comet

Nglish: Translation of comet for Spanish Speakers

Britannica English: Translation of comet for Arabic Speakers Encyclopedia article about comet

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