sidereal month


plural sidereal months
: the mean time of the moon's revolution in its orbit with reference to a star's position : 27 days, 7 hours, 43 minutes, 11.5 seconds of mean time
The Moon rotates on its axis once every 27.32166 days. This is the sidereal month and corresponds to the time taken for the average period of revolution of the Moon about the Earth.Stuart Ross Taylor

Word History

First Known Use

1833, in the meaning defined above

Time Traveler
The first known use of sidereal month was in 1833

Dictionary Entries Near sidereal month

Cite this Entry

“Sidereal month.” Dictionary, Merriam-Webster, Accessed 24 Apr. 2024.

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