sidereal day


noun Astronomy.

the interval between two successive passages of the vernal equinox over the meridian, being about four minutes shorter than a mean solar day.

Origin of sidereal day

First recorded in 1785–95
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British Dictionary definitions for sidereal day

sidereal day


noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012