Which of the criteria do astronomers use to classify an object as a planet?

Astronomers classify an object as a planet based on three main criteria: it must orbit a star (like the Sun), have sufficient mass for its self-gravity to shape it into a nearly round form, and have cleared its orbital path of other debris. This definition distinguishes planets from other celestial bodies, such as dwarf planets and asteroids. The criteria help ensure that planets are significant and stable objects within their solar systems.