mean sun


Definition of mean sun

: a fictitious sun used for timekeeping that moves uniformly along the celestial equator and maintains a constant rate of apparent motion equal to the average rate of apparent motion of the real sun

Examples of mean sun in a Sentence

Recent Examples on the Web This meant Sun, who had initially finished second, was moved into first place. Ben Church, CNN, "Controversial swimming star Sun Yang reacts angrily after opponent refuses to share podium," 23 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mean sun.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of mean sun

1765, in the meaning defined above

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Time Traveler

The first known use of mean sun was in 1765

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Cite this Entry

“Mean sun.” The Dictionary, Merriam-Webster Inc., Accessed 8 December 2019.

Comments on mean sun

What made you want to look up mean sun? Please tell us where you read or heard it (including the quote, if possible).


to constrict the range or activity of

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