Pluto(redirected from Not a planet)
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demote or devalue a person or thing; a pluto (not capitalized) is someone or something that has lost its status (On August 24, 2006, the International Astronomical Union, which decides the official names of all celestial bodies, stated that Pluto was not a true planet because it’s “too small and doesn’t dominate its neighborhood.” They dubbed Pluto a dwarf planet. This means that there are now only eight planets in the solar system.)
1. Roman Mythology The god of the dead and the ruler of the underworld, identified with the Greek Hades.
2. A dwarf planet having a sidereal period of revolution about the sun of 248.5 years, a highly elliptical orbit with a perihelion distance of 4.4 billion kilometers (2.8 billion miles) and an aphelion distance of 7.4 billion kilometers (4.6 billion miles), and a mean equatorial diameter of 2,302 kilometers (1,485 miles), less than half that of Earth. Until 2006, Pluto was classified as the ninth planet in the solar system. See Usage Note at planet.
(Classical Myth & Legend) classical myth the god of the underworld; Hades
(Celestial Objects) the second-largest dwarf planet in the solar system, located in the Kuiper belt; discovered in 1930 by Clyde Tombaugh (1906–97); classified as a planet until 2006, when it was reclassified as a dwarf planet. It has a diameter of 2390 km
1. to reduce (something) in status or importance
2. to put an end to (something)
[Latin, from Greek Ploutōn, literally: the rich one]
(Historical Terms) the code name of pipelines laid under the English Channel to supply fuel to the Allied forces landing in Normandy in 1944
[C20: from p(ipe)l(ine) u(nder) t(he) o(cean)]
2. the planet ninth in order from the sun, having an equatorial diameter of about 1400 mi. (2250 km), a mean distance from the sun of 3.674 billion mi. (5.914 billion km), a period of revolution of 248.53 years, and one known moon.
A dwarf planet that until 2006 was classified as the ninth planet in our solar system. It has a diameter about one-sixth that of Earth. It orbits the sun once every 248 years. Its orbit crosses that of Neptune. It has an average surface temperature of -369°F (-223°C). See Table at solar system. See Note at planet.
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|Noun||1.||Pluto - a cartoon character created by Walt Disney|
|2.||Pluto - (Greek mythology) the god of the underworld in ancient mythology; brother of Zeus and husband of Persephone|
Greek mythology - the mythology of the ancient Greeks
|3.||Pluto - a small planet and the farthest known planet from the sun; it has the most elliptical orbit of all the planets; "Pluto was discovered by Clyde Tombaugh in 1930"|
solar system - the sun with the celestial bodies that revolve around it in its gravitational field