SINCE 1828

An Encyclopædia Britannica Company

mean solar day

noun

Definition of mean solar day

:the interval between successive transits of a given meridian by the mean sun

First Known Use of mean solar day

1816

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WORD OF THE DAY

hew

play

to conform or adhere

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From the front hallways to the back rooms

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The History of the Word 'Terrorism'

Noah Webster first entered the term in 1840

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Words of the Year: 1066

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Irregardless

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The Exceptions Quiz III

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