from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Any of the four planets, Jupiter, Saturn, Uranus, and Neptune, with orbits outside that of Mars.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any planet of the Solar System whose orbit is located beyond the asteroid belt, i.e., any of Jupiter, Saturn, Uranus, or Neptune.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. (astronomy) a major planet whose orbit is outside the asteroid belt (Jupiter, Saturn, Uranus, Neptune, Pluto)
Sorry, no etymologies found.
From Zanzibar Twenty-a small outer planet five thousand million miles from a minor sun-in the Zanzibar system, thirty light years from Earth and thus about twenty from the carrier, a stream of rock and minerals and dirt dug from the soil, loosened by robot mining equipment and funneled through the box, spouted across space and into the box aboard the carrier and was deflected into the fuel bins.