The motion of any body, as a planet or satellite, in a
   curved line or orbit, until it returns to the same point again, or to a
   point relatively the same; -- designated as the annual, anomalistic,
   nodical, sidereal, or tropical revolution, according as the point of
   return or completion has a fixed relation to the year, the anomaly, the
   nodes, the stars, or the tropics; as, the revolution of the earth about
   the sun; the revolution of the moon about the earth.