trans-neptunian

listen to the pronunciation of trans-neptunian
İngilizce - İngilizce
Lying beyond the orbit of the planet Neptune (especially with regard to planetary bodies)
Located beyond the rim of the solar system

Planet X is a legendary trans-Neptunian world.

trans-Neptunian object
Any object (such as an asteroid, a planet, a KBO, or a star) in the Solar System with all or most of its orbit outside the orbit of Neptune
trans-neptunian