# Definition of leap year in US English:

## leap year

### noun

• A year, occurring once every four years, that has 366 days including February 29 as an intercalary day.

• ‘A common misconception is that the Gregorian modification states that a year will be a leap year if it is evenly divisible by 4, unless it is evenly divisible by 100.’
• ‘But 1600 and 2000 were leap years, because those year numbers are evenly divisible by 400.’
• ‘To make a calendar even better, new leap year rules have to be introduced, complicating the calculation of the calendar even more.’
• ‘I know leap years are roughly every four years, but I think there are some that aren't like that.’
• ‘On the advice of a Greek astronomer, Sosigenes, he then [thereafter] started the leap year system.’
• ‘First I'll present the code, then the rules for calculating which years are leap years, and finally the code again but with extensive comments interspersed.’
• ‘Therefore, the year 2000 will be a leap year, but the years 1700, 1800, and 1900 were not.’
• ‘Our calendar year is either 365 days in non leap years or 366 days in leap years.’
• ‘To compensate for this discrepancy, the leap year is omitted three times every four hundred years.’
• ‘There is really no reason for deviating from normal programming approaches for performing leap year calculations.’
• ‘I could just divide the number of days by 365 if I did not have to account for those leap years.’
• ‘If the year is not leap year nor festival year, then print the line ‘This is an ordinary year.’’
• ‘The Gregorian calendar's rules for leap years have three parts.’
• ‘To get even closer to the actual number, every 100 years is not a leap year, but every 400 years is a leap year.’
• ‘This means that 1700, 1800, and 1900 were not leap years, but 2000 was.’
• ‘To make a calendar a better measure of the Earth's orbit around the Sun, leap year rules were created and have since been modified.’
• ‘If a year is divisible by 4 and by 100, it is not a leap year unless it is also divisible by 400.’
• ‘It uses a globally accepted algorithm for determining which years are leap years.’
• ‘Thus, 1600 was a leap year, and 2000 will be, too, but 1700, 1800, and 1900 were not leap years.’
• ‘Therefore, the years 1700, 1800, 1900 and 2100 are not leap years, but 1600, 2000, and 2400 are leap years.’

### Origin

Late Middle English: probably from the fact that feast days after February in such a year fell two days later than in the previous year, rather than one day later as in other years, and could be said to have ‘leaped’ a day.

## leap year

/ˈlēp ˌyi(ə)r//ˈlip ˌjɪ(ə)r/