planet

noun4

1. •
   a huge round world in space, like the one we live on, that moves around a star
2. •
   construed with the or this: The Earth.
3. •
   (historical) Any body that orbits the Sun, including the asteroids (as minor planets) and sometimes the moons of those bodies (as satellite planets)

   • A Discovrse concerning a New Planet. Tending to prove, That 'tis probable our Earth is one of the Planets — 1640
4. •
   (historical) Each of the seven major bodies which move relative to the fixed stars in the night sky—the Moon, Mercury, Venus, the Sun, Mars, Jupiter and Saturn.

   • Be they not dreames of humane vanity,[…]to make of our knowne earth a bright shining planet [translating astre]? — 1603