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comet

[kom-it]
noun Astronomy.
  1. a celestial body moving about the sun, usually in a highly eccentric orbit, consisting of a central mass surrounded by an envelope of dust and gas that may form a tail that streams away from the sun.
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Origin of comet

1150–1200; Middle English comete < Anglo-French, Old French < Latin comētēs, comēta < Greek komḗtēs wearing long hair, equivalent to komē-, variant stem of komân to let one's hair grow (derivative of kómē hair) + -tēs agent suffix
Related formscom·et·ar·y [kom-i-ter-ee] /ˈkɒm ɪˌtɛr i/, co·met·ic [kuh-met-ik] /kəˈmɛt ɪk/, co·met·i·cal, adjectivecom·et·like, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for cometary

Historical Examples

  • Was the division of the cometary mass produced by the encounter?

    Meteoric astronomy:

    Daniel Kirkwood

  • Subsequently sodium and iron lines were found in cometary spectra.

    Curiosities of the Sky

    Garrett Serviss

  • That numerous facts—some observed in ancient and some in modern times—have been decidedly indicative of cometary disintegration.

    Comets and Meteors

    Daniel Kirkwood

  • Before entering the solar domain, they were doubtless members of a cometary system.

    Comets and Meteors

    Daniel Kirkwood

  • At one of these epochs the cometary orbit will probably undergo considerable transformation.

    Comets and Meteors

    Daniel Kirkwood


British Dictionary definitions for cometary

comet

noun
  1. a celestial body that travels around the sun, usually in a highly elliptical orbit: thought to consist of a solid frozen nucleus part of which vaporizes on approaching the sun to form a gaseous luminous coma and a long luminous tail
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Derived Formscometary or cometic (kɒˈmɛtɪk), adjective

Word Origin

C13: from Old French comète, from Latin comēta, from Greek komētēs long-haired, from komē hair
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for cometary

comet

n.

c.1200, from Old French comete (12c., Modern French comète), from Latin cometa, from Greek (aster) kometes, literally "long-haired (star)," from kome "hair of the head" (cf. koman "let the hair grow long"), of unknown origin. So called from resemblance of a comet's tail to streaming hair.

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Online Etymology Dictionary, © 2010 Douglas Harper

cometary in Science

comet

[kŏmĭt]
  1. A celestial object that orbits the Sun along an elongated path. A comet that is not near the Sun consists only of a nucleus-a solid core of frozen water, frozen gases, and dust. When a comet comes close to the Sun, its nucleus heats up and releases a gaseous coma that surrounds the nucleus. A comet forms a tail when solar heat or wind forces dust or gas off its coma, with the tail always streaming away from the Sun.Short-period comets have orbital periods of less than 200 years and come from the region known as the Kuiper belt. Long-period comets have periods greater than 200 years and come from the Oort cloud. See more at Kuiper belt Oort cloud. See Note at solar system.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

cometary in Culture

comet

An object that enters the inner solar system, typically in a very elongated orbit around the sun. Material is boiled off from the comet by the heat of the sun, so that a characteristic tail is formed. The path of a comet can be in the form of an ellipse or a hyperbola. If it follows a hyperbolic path, it enters the solar system once and then leaves forever. If its path is an ellipse, it stays in orbit around the sun.

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Note

Comets were once believed to be omens, and their appearances in the sky were greatly feared or welcomed.

Note

The most famous comet, Comet Halley (or Halley's comet), passes close to the Earth roughly every seventy-six years, most recently in 1986.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.