plan·​et | \ ˈpla-nət How to pronounce planet (audio) \

Definition of planet

1a(1) : any of the large bodies that revolve around the sun in the solar system
(2) : a similar body associated with another star
b : earth usually used with the one of the hottest places on the planet
c : any of the seven celestial bodies sun, moon, Venus, Jupiter, Mars, Mercury, and Saturn that in ancient belief have motions of their own among the fixed stars
2 : a celestial body held to influence the fate of human beings
3 : a person or thing of great importance : luminary
planet table

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Other Words from planet

planetlike \ ˈpla-​nət-​ˌlīk How to pronounce planetlike (audio) \ adjective

Synonyms for planet


earth, globe, world

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Did You Know?

Planet goes back to ancient Greek planēt- (literally, "wanderer"), which is derived from "planasthai," a Greek verb which means "to wander." The name "planet" was originally applied to any of seven visible celestial bodies which appeared to move independently of the fixed stars - the sun, the moon, Mercury, Venus, Mars, Jupiter, and Saturn. In the 17th century, "planet" began to be used specifically of the rocky or gaseous bodies that orbit around the sun - a definition which excluded the moon and, obviously, the sun, but included the Earth and, as they were discovered, Uranus, Neptune, and Pluto. In 2006, the International Astronomical Union developed a narrower definition of "planet," effectively demoting Pluto to the status of a "dwarf planet," a celestial body that is spherical and orbits the sun but is not large enough to disturb other objects from its orbit.

Examples of planet in a Sentence

our collective responsibility to conserve the planet and its natural resources for future generations

Recent Examples on the Web

The rest of the planet simply wasn’t ready — socially, culturally, financially — to embrace the sport at the levels from that glorious summer of ’99. San Diego Union-Tribune, "Column: Women’s soccer’s journey from promise of 1999 to reality of 2019," 11 June 2019 On June 10, Jupiter will be in opposition, meaning that the planet will be directly opposite of the sun, Nichols said. Nicole Stock,, "Grab your binoculars and head to the lake, Jupiter's moons will be visible this week," 10 June 2019 The 2019 Women's World Cup is upon us, with strength from all over the planet, from Europe, to North and South America, Asia and Oceania., "2019 Women's World Cup: Picking an All-Star European XI From Players at the Tournament," 7 June 2019 The hall depicts the creation of atoms, stars, galaxies and planets, and the search for extraterrestrial life. Robert D. Mcfadden, New York Times, "Dorothy and Lewis B. Cullman Hall of the Universe," 7 June 2019 Journalism is considered a crime in many places on this planet, and honest reporting is seen as a threat to authoritarian leaders who aim to control their people by limiting information and shutting the doors to the outside world. Annika Hernroth-rothstein, National Review, "I Was Kidnapped in Venezuela," 7 June 2019 The other is relativity, which is a theory of gravity and therefore of the universe at the largest scales—planets, stars and galaxies. The Economist, "How Einstein and Eddington stood against jingoism," 7 June 2019 Amateur astronomers from throughout the country will volunteer their time and telescopes to give visitors the opportunity to see planets, star clusters, the moon, nebulae and distant galaxies. Weldon Johnson, azcentral, "Grand Canyon National Park earns International Dark Sky Park status," 5 June 2019 Of all the video surveillance cameras on the planet, nearly half of them are in China. NBC News, "As the world commemorates Tiananmen Square, China is silent," 4 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'planet.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of planet

14th century, in the meaning defined at sense 1a

History and Etymology for planet

Middle English planete, from Anglo-French, from Late Latin planeta, modification of Greek planēt-, planēs, literally, wanderer, from planasthai to wander — more at floor

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Statistics for planet

Last Updated

17 Jun 2019

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Time Traveler for planet

The first known use of planet was in the 14th century

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More Definitions for planet


plan·​et | \ ˈpla-nət How to pronounce planet (audio) \

Kids Definition of planet

: any large heavenly body that orbits a star (as the sun)

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More from Merriam-Webster on planet

Rhyming Dictionary: Words that rhyme with planet

Thesaurus: All synonyms and antonyms for planet

Spanish Central: Translation of planet

Nglish: Translation of planet for Spanish Speakers

Britannica English: Translation of planet for Arabic Speakers Encyclopedia article about planet

Comments on planet

What made you want to look up planet? Please tell us where you read or heard it (including the quote, if possible).


having a desire to acquire more things

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