hour angle

noun

: the angle between the celestial meridian of an observer and the hour circle of a celestial object measured westward from the meridian

Word History

First Known Use

circa 1837, in the meaning defined above

Time Traveler

The first known use of hour angle was circa 1837

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Browse Nearby Words

hourage

hour angle

hour circle

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Cite this Entry

Style

“Hour angle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hour%20angle. Accessed 4 Nov. 2025.

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