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

Curves—squiggly lines through space, such as a comet’s trajectory or a stock market trend—are some of math’s simplest objects. —Joseph Howlett, Scientific American, 24 Feb. 2026

At the time of his death, he was focused on studying comets and astroids that could pose a hazard to Earth. —Clara Harter, Los Angeles Times, 20 Feb. 2026

Loeb has previously claimed that interstellar comet 3I/ATLAS could be an alien spaceship visiting our solar system. —Brett Tingley, Space.com, 20 Feb. 2026

Robotic probes proved increasingly versatile and successful, eventually visiting every planet in the solar system as well as a scattering of moons, comets, and asteroids. —New Atlas, 15 Feb. 2026

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