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

All the while, a mysterious comet streaks across the sky, growing larger by the day. —Zac Ntim, Deadline, 25 July 2025

Rubin is also expected to find more interstellar objects — such as ancient comet 3I/ATLAS. —Jamie Carter, Forbes.com, 24 July 2025

This material has been expelled from within a comet's nucleus — that means analyzing it with a technique called spectroscopy can tell astronomers what the rock and ice of that comet is composed of. —Robert Lea, Space.com, 23 July 2025

The comet that the Perseids meteor shower comes from was discovered in 1862 by Lewis Swift and Horace Tuttle, and aptly named 109P/Swift-Tuttle. —Stephanie Edwards, Discover Magazine, 15 July 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