sidereal day

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sidereal day

n.
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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

sidereal day

n
(Astronomy) See day5
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

side′real day′



n.
the interval between two successive passages of the vernal equinox over the meridian, being about four minutes shorter than a mean solar day.
[1785–95]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

sidereal 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.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.sidereal day - the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day
time unit, unit of time - a unit for measuring time periods
sidereal time - measured by the diurnal motion of stars
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
"As Oman is situated at latitude of about 23.5 degrees north, the day of autumn equinox is slightly offset by a few days, the period till the Autumn Equinox are called 'Equinoctial Days'.This is due to take place on September 28.