In the end stages of planet formation, a planet, as so defined, will have "cleared the neighbourhood" of its own orbital zone i.e. removed other bodies of comparable size. A large body that meets the other criteria for a planet but has not cleared its neighbourhood is classified as a dwarf planet. That includes Pluto, which is constrained in its orbit by the gravity of Neptune and shares its orbital neighbourhood with many Kuiper belt objects. The IAU's definition does not attach specific numbers or equations to this term, but all IAU-recognised planets have cleared their neighbourhoods to a much greater extent (by orders of magnitude) than any dwarf planet or candidate for dwarf planet.