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

Recent Examples of leap second from the Web

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.

First Known Use of leap second

1971


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