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outer planet

American  
[ou-ter plan-it] / ˈaʊ tər ˈplæn ɪt /

noun

Astronomy.
  1. any of the planets in our solar system whose orbits lie beyond the asteroid belt, namely, Jupiter, Saturn, Uranus, and Neptune: before its reclassification as a dwarf planet in 2006, Pluto was included among the outer planets.


outer planet British  

noun

  1. any of the planets Jupiter, Saturn, Uranus, Neptune, and (formerly) Pluto, whose orbit lies outside the asteroid belt

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

outer planet Scientific  
  1. Any of the four planets Jupiter, Saturn, Uranus, and Neptune, whose orbits lie outside that of Mars. The outer planets are large gas giants.

  2. Compare inner planet See also superior planet


Etymology

Origin of outer planet

First recorded in 1940–45

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Voyager 1 and its twin probe, Voyager 2, were launched in 1977 on a mission to explore the outer planets.

From New York Times

Those outer planets are also forcing the inner rocky planet into an eccentric orbit around the star that squeezes it as it orbits and rotates.

From Science Daily

These roles reflected how long it took each planet to orbit the Sun, lower speeds for the outer planets and higher speeds for the inner planets.

From Salon

Maybe we can convince them to go out into the solar system to mine the outer planets and harvest the sun’s energy.

From Scientific American

The Trojans, leftover chunks from the outer planets’ formation, are locked in stable orbits of the sun along the same path as the planet Jupiter.

From New York Times