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Synonyms

sidereal day

American  

noun

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


sidereal day British  

noun

  1. See day

"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

Etymology

Origin of sidereal day

First recorded in 1785–95

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Example Sentences

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So the solar day is about 4 minutes longer than the sidereal day.

From Textbooks • Oct. 13, 2016

However, astronomers also use a sidereal day, which is defined in terms of the rotation period of Earth with respect to the stars.

From Textbooks • Oct. 13, 2016

In a part of Earth’s orbit where Earth is moving faster than usual around the Sun, would the length of the sidereal day change?

From Textbooks • Oct. 13, 2016

Up to the mid-20th century, the sidereal day, the period of the earth’s rotation on its axis in relation to the stars, was used to determine standard time.

From Scientific American • Dec. 31, 2011

Then a sidereal day is three minutes fifty-six seconds shorter, than a solar day of twenty-four hours.

From Conversations on Natural Philosophy, in which the Elements of that Science are Familiarly Explained by Jones, Thomas P.