planet

noun
plan·et | \ˈpla-nət \

Definition of planet 

1a : 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

b(1) : any of the large bodies that revolve around the sun in the solar system

(2) : a similar body associated with another star

c : earth usually used with the

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 \ adjective

Synonyms for planet

Synonyms

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 atmosphere over the Arctic has warmed faster than any other region on the planet. John Timmer, Ars Technica, "Barents Sea seems to have crossed a climate tipping point," 26 June 2018 Which can make Journey feel a little bit, now, like the biggest, best, most ambitious cover band on the planet. Théoden Janes, charlotteobserver, "Concert review: Are Def Leppard and Journey getting too old for this kind of thing?," 10 June 2018 Summit, a new supercomputer unveiled at Oak Ridge National Lab is, unofficially for now, the most powerful calculating machine on the planet. Tom Simonite, WIRED, "The US Again Has World’s Most Powerful Supercomputer," 8 June 2018 Yet the global structure of soccer also hinges on individual star power and the argument over who is the best player on the planet is one that has attracted heated debate for the past decade. Martin Rogers, USA TODAY, "After World Cup, Cristiano Ronaldo and Lionel Messi may lose best player tags," 13 July 2018 Until 1909, nitrogen-fixing bacteria made most of the ammonia on the planet. Robert F. Service, Science | AAAS, "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon," 12 July 2018 The was no killer asteroid; the pieces of LA 2018 that made it to the planet’s surface were small. Joe Pappalardo, Popular Mechanics, "For Just 2nd Time Ever, Meteor Hunters Recover Chunks of Rock They Tracked From Space," 9 July 2018 From Finland to Mongolia, the Russian Empire and then, in somewhat different borders, the Soviet Union once ruled more than a sixth of the planet’s surface. Yaroslav Trofimov, WSJ, "Russia’s Turn to Its Asian Past," 6 July 2018 One of the most nutritious vegetables on the planet. Emily Hopkins, Cincinnati.com, "Your produce is less healthy than it was 70 years ago. These farmers might change that," 4 July 2018

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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Phrases Related to planet

preserve the planet

Statistics for planet

Last Updated

7 Oct 2018

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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

planet

noun
plan·et | \ˈpla-nət \

Kids Definition of planet

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

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