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.

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outer planet British  

noun

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

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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

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Etymology

Origin of outer planet

First recorded in 1940–45

Example Sentences

See Examples For:

outer planet

For every five orbits completed by the inner planet, the outer planet finishes almost exactly three.

From Science Daily ● Jun. 27, 2026

But the outer planet region is unsampled, so these stories remain a mystery.

From Slate ● Sep. 27, 2023

The star DMPP-1 hosts multiple planets with three inner planets—3.5 to 10 times the mass of the Earth—and one outer planet heavier than Neptune.

From Scientific American ● Dec. 23, 2019

But Nasa decided it could power Clipper with solar panels rather than the radioactive generators some other outer planet missions have used.

From BBC ● Mar. 23, 2017

Even if an outer planet were in the right place at the right time, we'd need fuel—a lot of fuel—to get into a braking orbit.

From Death Wish by Sheckley, Robert