planet

noun

plan·​et ˈpla-nət 

1

a(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

planetlike

ˈpla-nət-ˌlīk 

adjective

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 word 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 line with astronomical discovery and advancement, planet began to be used specifically of the rocky or gaseous bodies that orbit around the sun—a definition which excluded the moon and 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.

Synonyms

• earth
• globe
• world

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 first is the probability of life emerging on that planet given everything else that’s known about it. —Elise Cutts, WIRED, 7 Apr. 2024

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Turns out, a lot of the early, most effective methods for distressing denim in production, like sandblasting and pumice stone-tumbling, aren’t so great for people or the planet. —Jane Herman, Vogue, 7 Apr. 2024

Any celestial object like a moon or a planet that passes between two other bodies can create an eclipse by obscuring the view of objects like the sun. —Eric Lagatta, USA TODAY, 6 Apr. 2024

Hybridization may be a good thing in some cases, helping species adapt to a rapidly warming planet, said Daniel Rubinoff, an entomology professor and director of the University of Hawaii Insect Museum. —Ella Nilsen, CNN, 6 Apr. 2024

The comparison between them and the three planets comes naturally, also because Il Volo’s new album, Ad Astra, talks about stars and human fragility. —Billboard Italy, Billboard, 5 Apr. 2024

These planets conjunct approximately once every 14 years. —Skyler Caruso, Peoplemag, 5 Apr. 2024

Just moments after the baby is launched into space, his home planet of Krypton erupts violently, killing all of its inhabitants. —Khristopher J. Brooks, CBS News, 5 Apr. 2024

The solar system’s three other planets will be in the vicinity, but virtually impossible to see with the naked eye. —Marcia Dunn, Fortune, 5 Apr. 2024

Word History

Etymology

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

First Known Use

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

Phrases Containing planet

• inferior planet
• minor planet
• inner planet
• planet-stricken
• planet wheel
• superior planet
• preserve the planet
• outer planet
• planet-struck

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Kids Definition

planet

noun

plan·​et ˈplan-ət 

: a heavenly body other than a comet, asteroid, or satellite that travels in orbit around the sun

also : such a body orbiting another star

Etymology

Middle English planete "planet," from early French planet (same meaning), from Latin planeta (same meaning), from Greek planēt-, planēs "planet," literally, "wanderer"

Word Origin

Most of the stars seem to have fixed positions when they are compared to other stars. There are some heavenly bodies, however, that clearly change their positions in relation to the stars and to each other. They seem to wander about among the fixed stars. The ancient Greek name for such a heavenly body was planēs, which means "wanderer." The English word planet comes from the Greek planēs. Unlike the ancient Greeks, we now know that the planets "wander" across the sky because they are revolving around the sun.