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Webster 1913 Edition
Leap year
Leap′ yearˊ
Noun.
Bissextile; a year containing 366 days; every fourth year which leaps over a day more than a common year, giving to February twenty-nine days. See
Bissextile
. ☞ Every year whose number is divisible by four without a remainder is a leap year, excepting the full centuries, which, to be leap years, must be divisible by 400 without a remainder. If not so divisible they are common years. 1900, therefore, is not a leap year, but 2000 is.