comet

noun

com·et ˈkä-mət

: 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

cometary

ˈkä-mə-ˌter-ē

adjective

cometic

kə-ˈme-tik

kä-

adjective

Examples of comet in a Sentence

Recent Examples on the Web

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Every one of Kenny’s beats is a chunk of ore from a different comet. — Hattie Lindert, Pitchfork, 25 June 2026 In August, there’s also a comet that should be visible with small telescopes. — John Metcalfe, Mercury News, 3 July 2026 But with new information coming in from space telescopes, and astronomers eager to understand this object better, these clues are leading us closer and closer to the true origins of this strange comet. — Chelsea Gohd, Space.com, 24 June 2026 The observatory was named for fast-flying swift birds due to its ability to pivot rapidly to look at cosmic events and afterglows, enabling the study of comets, gravitational waves and black holes over long periods of time. — Ashley Strickland, CNN Money, 3 July 2026 See All Example Sentences for comet

Word History

Etymology

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

First Known Use

before the 12th century, in the meaning defined above

Time Traveler

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

See more words from the same century

Cite this Entry

Style

“Comet.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/comet. Accessed 8 Jul. 2026.

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Kids Definition

comet

noun

com·et ˈkäm-ət

: a bright heavenly body that develops a cloudy tail as it moves closer to the sun in its orbit

Etymology

Old English cometa "comet," from Latin cometa (same meaning), from Greek komētēs, literally, "long-haired," derived from komē "hair" — related to coma entry 2

comet

noun

Examples of comet in a Sentence

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comet

noun

Examples of comet in a Sentence

Word History

Rhymes for comet

Browse Nearby Words

Cite this Entry

Kids Definition

More from Merriam-Webster on comet

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