sidereal day(redirected from sidereal days)
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Related to sidereal days: sidereal time
The time required for a single rotation of the earth on its axis in reference to any star or to the vernal equinox at the meridian, equal to 23 hours, 56 minutes, 4.09 seconds in units of mean solar time.
(Astronomy) See day5
the interval between two successive passages of the vernal equinox over the meridian, being about four minutes shorter than a mean solar day.
A measure of time approximately equal to 23 hr, 56 min, 4.09 sec. A sidereal day represents the time needed for one complete rotation of the Earth on its axis.