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 starsb (1) : any of the large bodies that revolve around the sun in the solar system (2) : a similar body associated with another starc : 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
planetlikeplay \ˈpla-nət-ˌlīk\ adjective
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Examples of planet in a Sentence
our collective responsibility to conserve the planet and its natural resources for future generations
Recent Examples of planet from the Web
Saudi Arabia, one of the world’s largest per capita emitters of planet-warming emissions, has always been a reluctant participant in climate discussions.
New on DVD Power Rangers PG Five teens have been endowed with super powers but must unify to fight off alien invaders bent on destroying our planet Earth.
John Turturro is in Cuba, and calls his close personal friend Anthony Hopkins on the phone to inform him that there is a page in the Book of Kells that explains why the Transformer planet is about to collide with ours.
There just aren’t many franchise-level quarterbacks walking around the planet.
Ropeik tells me that because many lack confidence in Trump, people feel even less control over their own and the planet’s safety.
Bay might be spinning another tale of Autobot v. Decepticon in which the fate of the planet hangs in the balance, but his real battle is conquering you, the moviegoer.
College football was on a different planet in 1892.
Those edibles are some of the most powerful supplements on the planet: Lion’s mane supports brain function; maitake and shiitake benefit the cardiovascular system and may help prevent cancer.
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.
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.
PLANET Defined for Kids
Definition of planet for Students
: any large heavenly body that orbits a star (as the sun)
History for planet
Most stars seem to stay in fixed positions night after night. There are certain heavenly bodies, the planets, that look very much like stars but are not. They seem to wander about among the fixed stars. The ancient Greeks gave them the name planētes, meaning “wanderers.” The English word planet comes from this Greek word.
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