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Why are Kuiper belt objects also called trans-Neptunian objects?

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asteroid Ida and its satellite, Dactyl — Small body Asteroid Ida and its satellite, Dactyl, photographed by the Galileo spacecraft on August 28, 1993, from a distance of about 10,870 km (6,750 miles). Ida is about 56 km (35 miles) long and shows the irregular shape and impact craters characteristic of many asteroids. The Galileo image revealed that Ida is accompanied by a tiny companion about 1.5 km (1 mile) wide, the first proof that some asteroids have natural satellites.

Kuiper belt objects (KBOs) are referred to as trans-Neptunian objects (TNOs) because their orbits lie entirely or primarily beyond the orbit of the planet Neptune.12

The term "trans-Neptunian" is descriptive, derived from the Latin prefix trans- (meaning "across" or "beyond") and the name of the planet Neptune. Since KBOs maintain a mean distance from the Sun greater than Neptune’s mean orbital distance of approximately 30 astronomical units, they are categorized by this spatial relationship to the outermost major planet in our solar system.312