outer planet


noun Astronomy.

any of the four planets with orbits outside the orbit of Mars, namely, the planets Jupiter, Saturn, Uranus, and Neptune.
Compare inner planet.

Origin of outer planet

First recorded in 1940–45

Example sentences from the Web for outer planet

  • I've heard of it, but as this is my first outer-planet voyage, I know nothing about it.

    The Sargasso of Space |Edmond Hamilton

British Dictionary definitions for outer planet

outer planet

noun

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

Scientific definitions for outer planet

outer planet

Any of the four planets Jupiter, Saturn, Uranus, and Neptune, whose orbits lie outside that of Mars. The outer planets are large gas giants. Compare inner planet. See also superior planet.