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 most productive viewing generally comes after midnight, when Earth’s rotation turns observers into the incoming stream of comet debris. — Jamie Carter, Forbes.com, 25 July 2026

Unlike rocky asteroids, comets can subtly change course as gas escaping from their surfaces acts like tiny thrusters. — Samantha Mathewson, Space.com, 22 July 2026

When comets come around the sun, the dust emitted as the debris collides with Earth's atmosphere forms a trail that creates fiery, colorful streaks in the sky, according to NASA. — Julia Jacobo, ABC News, 21 July 2026

This year, the Perseid meteor shower is predicted to peak on the night of August 12 into the early morning of August 13, when Earth travels through the most dense and dusty part of the comet debris. — Michele Laufik, Martha Stewart, 17 July 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