comet

noun
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

But imaging didn't show any indication of gas and dust being released, as is typical when a comet approaches the Sun. John Timmer, Ars Technica, "Visitor from another solar system accelerated away from the Sun," 28 June 2018 Might the star have been a comet, blazing past Earth the way Hale-Bopp did in 1997? Kyle Peterson, WSJ, "An Astronomer’s View of the Christmas Sky," 21 Dec. 2018 But recent research found that ’Oumuamua isn’t a comet. Avery Thompson, Popular Mechanics, "Scientists Speculate Interstellar Comet Could Be a Solar Sail," 6 Nov. 2018 As with methane, there could well be non-biological explanations for the presence of carbon-containing molecules on Mars, such as geologic processes or impacts by asteroids, comet, meteors and interplanetary dust. Marcia Dunn, chicagotribune.com, "New Mars discoveries in ancient lakebed advance case for possible life," 7 June 2018 In recent decades, scientists have tossed around the idea that Pluto could be a giant comet. Julissa Treviño, Smithsonian, "Is Pluto Actually a Mash-up of a Billion Comets?," 30 May 2018 Like bugs hitting the windshield of a fast-moving car, meteors pelt Earth when the planet passes through a particularly dense part of the stream of debris left behind by a comet. Andrew Fazekas, National Geographic, "How to See the 2018 Lyrid Meteor Shower," 20 Apr. 2018 Astronomy images span a phenomenal range scale, from things that would fit neatly on Earth (like comets or features on local bodies) to the mind-bogglingly large (like stellar nurseries or entire galaxies). John Timmer, Ars Technica, "Some good came out of 2018: Astronomy photos," 11 Nov. 2018 Earth will pass through the thickest part of the comet's trail during the daytime hours on Aug. 12, which is why the nights before and after are the Perseids' peak. Sarah Lewin, Space.com, "The 2018 Perseid Meteor Shower Promises Spectacular Views This Week," 6 Aug. 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

22 Feb 2019

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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

comet

noun

English Language Learners Definition of comet

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

comet

noun
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

Spanish Central: Translation of comet

Nglish: Translation of comet for Spanish Speakers

Britannica English: Translation of comet for Arabic Speakers

Britannica.com: Encyclopedia article about comet

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