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A planetary system consists of the non-stellar objects orbiting a star. Of current observational interest are planets and circumstellar disks, but systems are also presumed to have bodies too small to be observed given their distance, given the example of the solar system. The term planet multiplicity refers to the number of planets, e.g., eight for the solar system.
The term stellar system has been used with a similar meaning, but including the star and any binary companion. (However stellar system is often used specifically for multiple stars gravitationally bound.) A planetary system may include individual planets that orbit different binary companions or that orbit more than one companion, i.e., circumbinary planets.