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

He says he is extra lucky around his leap year birthdays, winning competitions in the past.

From BBC • Feb. 28, 2024

The extra accrued time results in Feb. 29 appearing on the calendar every fourth year — leap year — to help the seasons line up.

From Los Angeles Times • Feb. 28, 2024

Even today, some calendars discount the leap year meant to keep us in time with our orbit, while others ignore the sun altogether.

From National Geographic • Feb. 26, 2024

It remains in use today and, clearly, isn’t perfect or there would be no need for leap year.

From Seattle Times • Feb. 24, 2024

“The twenty-ninth of February. She wanted to get married on the leap year because she knew no other woman in her right mind would want to do it.”

From "Native Speaker" by Chang-rae Lee