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 comet passed and survived its closest point to the sun, known as perihelion, on Jan. 13, 2025. —Brett Tingley, Space.com, 5 Feb. 2025

Messier was interested in comets, so his list was a set of fuzzy objects that might be mistaken for comets. —Chris Impey, The Conversation, 24 Jan. 2025

Lynskey moves smoothly from apocalyptic tales about comets and asteroids to killer robots and infected zombies. —Jennifer Szalai, New York Times, 22 Jan. 2025

The film centers around two astronomers desperately attempting to alert humanity of a planet-ending comet, a metaphor for climate change and a satirical take on media and political response to the climate crisis. —Charisma Madarang, Rolling Stone, 17 Jan. 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

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