noun: (astronomy) A region of space between 30 and 50 astronomical units from the Sun, roughly confined within a thick band around the ecliptic of the Solar System. This area is populated by many thousands of trans-Neptunian objects.
noun: (astronomy) a type of asteroid belt found in the outer regions of planetary systems that forms an annular belt or disc around the system's center, lying beyond the planetary formation region for major planets, which may extend outwards to reach the inner Oort cloud
noun: Alternative letter-case form of Kuiper belt [(astronomy) A region of space between 30 and 50 astronomical units from the Sun, roughly confined within a thick band around the ecliptic of the Solar System. This area is populated by many thousands of trans-Neptunian objects.]