ephemeris time


: a uniform measure of time defined by the orbital motions of the planets

Word History

First Known Use

1950, in the meaning defined above

Time Traveler
The first known use of ephemeris time was in 1950

Dictionary Entries Near ephemeris time

Cite this Entry

“Ephemeris time.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ephemeris%20time. Accessed 21 Feb. 2024.

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