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 bunker brass now believe their best bet for survival lies on the surface, inside the giant crater left behind by the world-ending comet. —Mike Miller, Entertainment Weekly, 25 Sep. 2025

Telescope observations reveal how comet has changed What is asteroid 2024 YR4? —Eric Lagatta, USA Today, 24 Sep. 2025

No, not little green men, but rather deep-space wanderers like the peculiar comet 3I/ATLAS discovered this summer. —Stefanie Waldek, Space.com, 17 Sep. 2025

October is also a peak month for displays of the Northern Lights; if geomagnetic activity is high, some observers at northern latitudes may also see the comet amid auroras. —Jamie Carter, Forbes.com, 10 Sep. 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