Definitionen
1.NounA planet with a moon large enough to be considered a planet, were the planet not there, having a substantial portion of the system's overall mass.
2.NounA pair of planemos in orbit around each other, where the barycenter of their orbits lies outside of both planemos, which in turn is in orbit about a star.
3.NounA pair of planemos in orbit around each other, where the barycenter of their orbits lies outside of both planemos.
4.NounA planemo with a moon large enough to be considered a planemo, having a substantial portion of the system's overall mass.