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Related to leap second: leap year
A second of time, as measured by an atomic clock, added to or omitted from official timekeeping systems periodically to compensate for small changes in the rotation of the earth and therefore the length of a solar day.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
(Units) a second added to or removed from a scale for reckoning time on one particular occasion, to synchronize it with another scale
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
an extra second intercalated into the world's timekeeping system about once a year, made necessary by the gradual slowing down of the earth's rotation.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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|Noun||1.||leap second - a second (as measured by an atomic clock) added to or subtracted from Greenwich Mean Time in order to compensate for slowing in the Earth's rotation|
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