leap year
  • noun a year occurring every four years in which an extra day has to be added because there are 365.25 days in a year
  • (written as Leap Year)
    Year in which an extra day has to be added because of the fact that there are about 365.25 days in a year. An extra day, the leap day, every four years keeps the calendar almost correct, although it is omitted when the year is a round century not divisible by 400, for extra accuracy.

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