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 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).
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Brian Resnick, Vox, "The summer solstice is coming: 9 things to know about the longest day of the year," 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).
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Brian Resnick, Vox, "The summer solstice is coming: 9 things to know about the longest day of the year," 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).
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Brian Resnick, Vox, "The summer solstice is coming: 9 things to know about the longest day of the year," 14 June 2019 This time, Mendoza crushed a hard line drive over a leaping second baseman Brandt Broussard.
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Brody Miller, nola.com, "‘Devastated’ and teary-eyed, LSU ends expectation-filled season shy of Omaha goals," 9 June 2019 This is unlikely to ever be used, since there has never been a negative leap second.
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Peter Bright, Ars Technica, "Windows 10 will get better at telling time with new leap second support," 19 July 2018 Technically, there can also be negative leap seconds, should UTC ever get more than 0.9 seconds ahead of atomic time.
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Peter Bright, Ars Technica, "Windows 10 will get better at telling time with new leap second support," 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).
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Brian Resnick, Vox, "The winter solstice is Friday: 8 things to know about the shortest day of the year," 18 Dec. 2018 Every time the gap is more than 0.9 seconds, an extra second is added to UTC—a leap second—to bring the two back in sync.
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Peter Bright, Ars Technica, "Windows 10 will get better at telling time with new leap second support," 19 July 2018
See MoreThese 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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Time Traveler for leap second
The first known use of leap second was in 1971
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