asteroid [asteroids](astronomy: a naturally occurring solid object, which is smaller than a planet and is not a comet, that orbits a star) noun [UK: ˈæ.stə.rɔɪd] [US: ˈæ.stə.ˈrɔɪd]What's the difference between asteroids and comets? = Qual è la differenza tra asteroidi e comete?
planetoid [planetoids](any of several larger astral bodies) noun [UK: ˈplæ.nɪ.tɔɪd] [US: ˈplæ.nɪ.ˌtɔɪd]