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planetoid

Definitions of planetoid
  1. noun
    any of numerous small celestial bodies that move around the sun
    synonyms: minor planet
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    examples:
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    Quaoar
    a planetoid discovered in 2002
    Sedna
    a planetoid of rock and ice about three-quarters the size of Pluto discovered in 2003; the most distant object known to orbit around the sun
    Apollo asteroid
    an asteroid whose orbit crosses the Earth's orbit
    Ceres
    the largest asteroid and the first discovered
    Pallas
    a large asteroid; the second asteroid to be discovered
    Vesta
    the brightest asteroid but the fourth to be discovered
    types:
    asteroid
    any of numerous small celestial bodies composed of rock and metal that move around the sun (mainly between the orbits of Mars and Jupiter)
    KBO, Kuiper belt object
    any of many minor planets in the Kuiper belt outside the orbit of Neptune at the edge of the solar system
    Chiron
    an asteroid discovered in 1977; it is unique in having an orbit lying mainly between the orbits of Saturn and Uranus
    type of:
    celestial body, heavenly body
    natural objects visible in the sky
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