Original: Ixion is a plutino (an object that has a 2:3 orbital resonance with Neptune) and a potential dwarf planet; its estimated diameter of 800 km makes it the third largest plutino.
Simplified: Ixion is a plutino (an object that has a 2:3 orbital resonance with Neptune) and could be a dwarf planet. Astronomers think that it has a diameter of about 800 km, which makes it the third biggest plutino.