ephemeris time

noun

Definition of ephemeris time

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

First Known Use of ephemeris time

1950, in the meaning defined above

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The first known use of ephemeris time was in 1950

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Dictionary Entries Near ephemeris time

ephemeris

ephemeris time

ephemeron

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Cite this Entry

“Ephemeris time.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ephemeris%20time. Accessed 16 Aug. 2022.

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More from Merriam-Webster on ephemeris time

Britannica.com: Encyclopedia article about ephemeris time

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