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

Many scientists believe the planet is experiencing its sixth mass extinction in the past half-billion years, the first since the dinosaurs were lost 65 million years ago. Keith Matheny, Detroit Free Press, "Michigan's most endangered species nears extinction in Oakland County," 13 July 2018 In another major setback for conservation, the last remaining male northern white rhino on the planet died in March in Kenya, leaving conservationists struggling to save that sub-species using in vitro fertilization. Washington Post, "8 endangered black rhinos die in Kenya after relocation," 13 July 2018 In another major setback for conservation, the last remaining male northern white rhino on the planet died in March in Kenya, leaving conservationists struggling to save that sub-species using in vitro fertilization. Khaled Kazziha, chicagotribune.com, "8 endangered black rhinos die in Kenya after relocation," 13 July 2018 Telescope planet viewing The Adler Planetarium will bring its telescope for free viewings of Venus and Jupiter from 2 to 4 p.m. Sunday, July 15, at Craftsman by Two Brothers, 16 W. Jefferson Ave. Michelle Mullins, Naperville Sun, "This Week in Naperville," 13 July 2018 In another major setback for conservation, the last remaining male northern white rhino on the planet died in March in Kenya, leaving conservationists struggling to save that sub-species using in vitro fertilization. Khaled Kazziha, Fox News, "7 endangered rhinos die in Kenya relocation bid: Official," 13 July 2018 Mars will also appear hazy because of a large dust storm now swirling around the planet. Meg Jones, Milwaukee Journal Sentinel, "Night sky brings a treat this month as Mars is the brightest it has been in 15 years," 13 July 2018 As that galaxy’s gas, dust, stars, and possible planets grind together, jets of X-rays, radio waves, and ultra-high-energy particles blast out. Ian Haydon, Philly.com, "For the first time, scientists harness 'ghost particles' to study the universe and its black holes," 12 July 2018 Astronomers now believe that there is at least one planet orbitting every star in the sky. Alvaro Montano, Houston Chronicle, "Planet Hockey offers young players chance to improve skill set at Willowbrook camp," 11 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

21 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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Comments on planet

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a state of commotion or excitement

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