leap second

1. 1.

   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

   Broadersecond

Questions about leap second

What does leap second mean?

leap second means "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".

Is leap second a common word?

leap second is banded "Rare" — specialist or archaic — most readers will not have met it. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.