sidereal
81sidereal period — noun Astronomy the period of revolution of one body about another, measured with respect to the distant stars …
82sidereal time — noun Astronomy time reckoned from the motion of the earth (or a planet) relative to the distant stars (rather than with respect to the sun) …
83sidereal day — side′real day′ n. astron. the interval between two successive passages of the vernal equinox over the meridian, being about four minutes shorter than a mean solar day • Etymology: 1785–95 …
84sidereal month — side′real month′ n. astron. month • Etymology: 1865–70 …
85sidereal time — side′real time′ n. astron. time measured by the diurnal motion of stars • Etymology: 1805–15 …
86sidereal year — side′real year′ n. astron. year 4), c) • Etymology: 1675–85 …
87sidereal day — /saɪˌdɪəriəl ˈdeɪ/ (say suy.dearreeuhl day) noun See day (def. 3e) …
88sidereal period — /saɪˌdɪəriəl ˈpɪəriəd/ (say suy.dearreeuhl pearreeuhd) noun (of a planet) the time taken to complete one revolution of the sun with reference to the fixed stars …
89sidereal year — /saɪˌdɪəriəl ˈjɪə/ (say suy.dearreeuhl year) noun See year (def. 6) …
90Sidereal Day — The true rotation period of a planet, determined by the time between appearances of a star in the same place in the sky. Since the rotation of the Earth is gradually slowing down, a day in the past was shorter than now, and in the future it… …
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