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

Topline After a quiet 2025 for comets, skywatchers may soon get a very special naked-eye spectacle in the shape of Comet Lemmon (C/2025 A6). —Jamie Carter, Forbes.com, 10 Sep. 2025

Thanks to this description of the relationships between these elements, Newton was able to explain a number of phenomena, such as the shape of the planets’ orbits, how the Moon causes the Earth’s tides, and why comets appear and disappear from the sky. —Big Think, 9 Sep. 2025

The comet will also be positioned about 2 degrees to the left of the second magnitude star Izar, also in Boötes. —Joe Rao, Space.com, 8 Sep. 2025

For Olympians who want to be more than a fleeting comet, a steady stream of content is necessary. —Daniel Kaplan, HollywoodReporter, 21 Aug. 2025

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

Rhymes for comet

• grommet
• vomit
• recommit

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