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sidereal hour

noun

: the 24th part of a sidereal day

Word History

First Known Use

circa 1695, in the meaning defined above

Time Traveler
The first known use of sidereal hour was circa 1695

Rhymes for sidereal hour

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Browse Nearby Words

sidereal day
sidereal hour
sidereal hour angle
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Cite this Entry

“Sidereal hour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sidereal%20hour. Accessed 27 Nov. 2025.

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