Definition of LEAP SECOND (original) (raw)
: an intercalary second added to Coordinated Universal Time to compensate for the slowing of the earth's rotation and keep Coordinated Universal Time in synchrony with solar time
Examples of leap second in a Sentence
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Like my wife, the world’s timekeepers have been forced to adjust their clocks, adding thirty-seven leap seconds since 1972. —
Joshua Rothman, The New Yorker, 29 Oct. 2024 Few computer programs are written to allow for a negative leap second. —Mark Fischetti, Scientific American, 15 Oct. 2024 Perhaps this should hasten the _leap second_’s demise. —Lara Williams, The Mercury News, 26 July 2024 While leap seconds have largely been absorbed into current mechanisms, experts say, a negative leap second — or, a minute with only 59 seconds — could pose an entirely new challenge. —Bill Chappell, NPR, 30 Mar. 2024 [See all Example Sentences for _leap second_ 
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Word History
First Known Use
1971, in the meaning defined above
Time Traveler
The first known use of leap second was in 1971
Dictionary Entries Near leap second
Cite this Entry
“Leap second.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/leap%20second. Accessed 20 Jan. 2025.
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