Definition of a planet or "how pluto lost it's status"

New definition of a planet:

1. Has sufficient mass to contract to a sphere.
   
2. Orbits a sun.
   
3. Has cleared material in it's orbit.

And so:

• Inner rocky planets:
  Mercury, Venus, Earth, Mars. 
  
• Gas giants:
  Saturn, Uranus, Neptune.
  
• Dwarf planets and the Kuiper belt
  Pluto, Ares, Kuiper-Oort, etc.