com·et | \ ˈkä-mət \

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 \ adjective
cometic \kə-ˈme-tik, kä- \ adjective

Examples of comet in a Sentence

Recent Examples on the Web

Organic molecules are being found in comets and cosmic clouds. Jamie Seidel, Fox News, "Wild new alien theory emerges," 28 June 2018 The compound is stirred into the comet at its formation, a fingerprint of the early planetary system. Nola Taylor Redd, Scientific American, "Interstellar Mystery Object Now Thought to Be a Comet," 27 June 2018 Every year in August, the Swift-Tuttle comet puts on a brilliant show. Brian Resnick, Vox, "Summer is for meteor showers and stargazing. Here’s how to watch.," 22 June 2018 On June 8, 2017, a story published by The Oregonian/OregonLive became the comet that ricocheted 'round the baseball universe and beyond. Ron Richmond For The Oregonian/oregonlive,, "Inside Luke Heimlich's senior season with the Oregon State baseball team," 8 June 2018 The debris left behind by the comet burns up in our atmosphere creating fiery streaks observed in the night sky. Sarah Gray, Fortune, "The 2018 Lyrid Meteor Shower Will Light Up the Sky on Earth Day. Here Are the Best Places to See It," 17 Apr. 2018 Megadeath in the Yucatán The first comet was discovered in the 17th century—although comet-like objects have been sighted throughout history, showing up in biblical and other ancient accounts. Nina Burleigh, Newsweek, "We Can Save Ourselves From Earth-Killing Asteroids, But Someone Has to Pay," 11 June 2015 The gap in their arrivals approximates the gap between appearances by Halley’s Comet, the most famous of the thousands of comets that streak through our solar system. Tom Verducci,, "The Star That Still Won't Shine: The Incredible, Unprecedented but Unseen Greatness of Mike Trout," 12 July 2018 Whatever this means, Fortnite has continues to maintain the enormous momentum introduced by last season’s comet, as most players are thrilled to try to solve the newest mystery. Patricia Hernandez, The Verge, "Fortnite’s new rifts are slowly consuming the map," 2 July 2018

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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Statistics for comet

Last Updated

20 Sep 2018

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Time Traveler for comet

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

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More Definitions for comet



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 \

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

Spanish Central: Translation of comet

Nglish: Translation of comet for Spanish Speakers

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

Comments on comet

What made you want to look up comet? Please tell us where you read or heard it (including the quote, if possible).


to deposit or conceal in a hiding place

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