leap year

American  

noun

1. (in the Gregorian calendar) a year that contains 366 days, with February 29 as an additional day: occurring in years whose last two digits are evenly divisible by four, except for centenary years not divisible by 400.

2. a year containing an extra day or extra month in any calendar.

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leap year British  

noun

1. a calendar year of 366 days, February 29 ( leap day ) being the additional day, that occurs every four years (those whose number is divisible by four) except for century years whose number is not divisible by 400. It offsets the difference between the length of the solar year (365.2422 days) and the calendar year of 365 days

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Etymology

Origin of leap year

1350–1400; Middle English lepe yere

Example Sentences

The reason of which I conceive to be, to keep it equal to the course of the Sun, as our Leap year doth.

From An Historical Relation of the Island Ceylon in the East Indies Together with an Account of the Detaining in Captivity the Author and Divers other Englishmen Now Living There, and of the Author's Miraculous Escape by Knox, Robert

Leap year was never a gude sheep year.

From The Proverbs of Scotland by Hislop, Alexander

Thirty days hath September, April, June, and November; All the rest have thirty-one, Save February, which alone Hath twenty-eigth, except Leap year, And twenty-nine is then its share.

From The Infant System For Developing the Intellectual and Moral Powers of all Children, from One to Seven years of Age by Wilderspin, Samuel