A type of dwarf planet orbiting the Sun beyond Neptune. The name was introduced by the International Astronomical Union in 2008. In their official definition, a plutoid is a celestial body in orbit around the Sun at a semimajor axis greater than that of Neptune that has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (near-spherical) shape, and that has not cleared the neighbourhood around its orbit. Satellites of plutoids are not themselves plutoids, even if they are massive enough to be rounded in shape. The first four named plutoids are Pluto, Eris, Haumea, and Makemake.