'Planet' definitions:

Definition of 'planet'

From: WordNet
noun
(astronomy) any of the nine large celestial bodies in the solar system that revolve around the sun and shine by reflected light; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto in order of their proximity to the sun; viewed from the constellation Hercules, all the planets rotate around the sun in a counterclockwise direction [syn: planet, major planet]
noun
A person who follows or serves another [syn: satellite, planet]
noun
Any celestial body (other than comets or satellites) that revolves around a star

Definition of 'Planet'

From: GCIDE
  • Planet \Plan"et\, n. [OE. planete, F. plan[`e]te, L. planeta, fr. Gr. ?, and ? a planet; prop. wandering, fr. ? to wander, fr. ? a wandering.]
  • 1. (Astron.) A celestial body which revolves about the sun in an orbit of a moderate degree of eccentricity. It is distinguished from a comet by the absence of a coma, and by having a less eccentric orbit. See Solar system. [1913 Webster]
  • Note: The term planet was first used to distinguish those stars which have an apparent motion through the constellations from the fixed stars, which retain their relative places unchanged. The inferior planets are Mercury and Venus, which are nearer to the sun than is the earth; the superior planets are Mars, the asteroids, Jupiter, Saturn, Uranus, and Neptune, which are farther from the sun than is the earth. Primary planets are those which revolve about the sun; secondary planets, or moons, are those which revolve around the primary planets as satellites, and at the same time revolve with them about the sun. [1913 Webster]
  • 2. A star, as influencing the fate of a men. [1913 Webster]
  • There's some ill planet reigns. --Shak. [1913 Webster]
  • Planet gear. (Mach.) See Epicyclic train, under Epicyclic.
  • Planet wheel, a gear wheel which revolves around the wheel with which it meshes, in an epicyclic train. [1913 Webster]