sidereal time


: time based on the sidereal day
: the hour angle of the vernal equinox at a place

Example Sentences

Recent Examples on the Web The space traveler is a multi-complication pocket watch, with double-wheel escapement, mean solar and sidereal time, an annual calendar, age and phase of the moon and the equation of time. Carol Besler, Robb Report, 4 Jan. 2023 The pink gold masterpiece includes 12 complications, including a cathedral minute repeater, tourbillon, perpetual calendar with retrograde date, moon age and angular motion, sidereal time and sky chart. Carol Besler, Robb Report, 5 Jan. 2023 The sky chart is a disk that rotates at a speed of sidereal time (23 hours, 56 minutes and 4 seconds). Roberta Naas, Forbes, 7 Apr. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sidereal time.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1765, in the meaning defined at sense 1

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

Dictionary Entries Near sidereal time

Cite this Entry

“Sidereal time.” Dictionary, Merriam-Webster, Accessed 21 Mar. 2023.

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