leap second

noun

Definition of leap second

: 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 But the overall trend in recent decades is a slower spin, meaning changing leap second policy cuts both ways: adding and subtracting a second, depending on the year. Caroline Delbert, Popular Mechanics, 11 Jan. 2021 Eventually, the effects of tidal friction should overcome all those other factors, and Earth’s days will get longer and longer as its rotation keeps slowing (forcing timekeepers to add leap seconds to the calendar periodically). Brian Resnick, Vox, 14 June 2019 Eventually, the effects of tidal friction should overcome all those other factors, and Earth’s days will get longer and longer as its rotation keeps slowing (forcing timekeepers to add leap seconds to the calendar periodically). Brian Resnick, Vox, 14 June 2019 Eventually, the effects of tidal friction should overcome all those other factors, and Earth’s days will get longer and longer as its rotation keeps slowing (forcing timekeepers to add leap seconds to the calendar periodically). Brian Resnick, Vox, 14 June 2019 This time, Mendoza crushed a hard line drive over a leaping second baseman Brandt Broussard. Brody Miller, nola.com, 9 June 2019 This is unlikely to ever be used, since there has never been a negative leap second. Peter Bright, Ars Technica, 19 July 2018 Technically, there can also be negative leap seconds, should UTC ever get more than 0.9 seconds ahead of atomic time. Peter Bright, Ars Technica, 19 July 2018 Eventually, the effects of tidal friction should overcome all those other factors, and Earth’s days will get longer and longer as the planet’s rotation keeps slowing (forcing timekeepers to add leap seconds to the calendar periodically). Brian Resnick, Vox, 18 Dec. 2018

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

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First Known Use of leap second

1971, in the meaning defined above

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Time Traveler for leap second

Time Traveler

The first known use of leap second was in 1971

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Cite this Entry

“Leap second.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/leap%20second. Accessed 15 Jun. 2021.

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