sidereal hour

noun

Definition of sidereal hour

: the 24th part of a sidereal day

First Known Use of sidereal hour

circa 1695, in the meaning defined above

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Time Traveler for sidereal hour

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The first known use of sidereal hour was circa 1695

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Cite this Entry

“Sidereal hour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sidereal%20hour. Accessed 28 Oct. 2020.

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