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

The mission's accomplishments include discovering evidence of galactic mergers, identifying new star clusters, tracking hundreds of thousands of asteroids and comets, and helping discover exoplanets and black holes. —Julian Dossett, Space.com, 27 Mar. 2025

The Near-Earth Object (NEO) Surveyor is a $1.4-billion infrared telescope with a single mission: to hunt asteroids and comets that could pose a danger to Earth. —Corinne Purtill, Los Angeles Times, 26 Mar. 2025

This flyby is part of a series of five near-Earth approaches currently being closely monitored by NASA's Asteroid Watch Dashboard, a tool that tracks asteroids and comets making relatively close passes to our planet. —Thomas G. Moukawsher, Newsweek, 20 Mar. 2025

At night, the illuminated cars are designed to look like comets zipping through the sky, on tracks without external lighting. —Eve Chen, USA TODAY, 4 Mar. 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