sidereal year


plural sidereal years
: the time in which the earth completes one revolution in its orbit around the sun measured with respect to the fixed stars : 365 days, 6 hours, 9 minutes, and 9.5 seconds of mean time
The light-year is defined as the distance light travels in 1 sidereal yearWilliam D. Johnstone

Word History

First Known Use

1765, in the meaning defined above

Time Traveler
The first known use of sidereal year was in 1765

Dictionary Entries Near sidereal year

Cite this Entry

“Sidereal year.” Dictionary, Merriam-Webster, Accessed 25 Jun. 2024.

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