mean solar day

American  

noun

1. Astronomy. the average length of an apparent solar day, very closely approximating 24 hours, as calculated over one full year.

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mean solar day British  

noun

1. the time between two successive passages of the mean sun across the meridian at noon. It is equal to 24 hours 3 minutes and 56.555 seconds of mean sidereal time

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mean solar day Scientific  

1. See under solar time

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Example Sentences

A mean solar day contains exactly 24 hours and is what we use in our everyday timekeeping.

From Textbooks • Oct. 13, 2016

For many years it was defined as 1/86,400 of a mean solar day.

From Textbooks • Aug. 12, 2015

A mean solar day — based on the time it takes the Earth to rotate once — is calculated to be 86,400 seconds.

From New York Times • Jun. 30, 2015

The sidereal day and the mean solar day necessitate some means of registering time, such as clocks; therefore the original day in use must have been the apparent solar day.

From The Astronomy of the Bible An Elementary Commentary on the Astronomical References of Holy Scripture by Maunder, E. Walter (Edward Walter)

The length of the sidereal day is to the mean solar day as .99727 to 1, and various attempts have been made by trains of wheels to obtain this relation—but all are somewhat complicated.

From Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 5 "Clervaux" to "Cockade" by Various