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ephemeris second
Word Origin
noun
,
Astronomy.
1.
the unit of ephemeris time, defined as a precise fraction of the length of the tropical year 1900.
Origin of
ephemeris second
Expand
1965-1970
First recorded in
1965-70
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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Difficulty index for
ephemeris second
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Word Value for
ephemeris
0
17
Scrabble
Words With Friends
Nearby words for ephemeris second
ephemerae
ephemeral
ephemerality
ephemerid
ephemeris
ephemeris second
ephemeris time
ephemeron
ephemeropteran
ephemerous
ephes.
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