Leap Day 2024: Why is February 29 so called in English?

In 2024, we're in a leap year: why there's a February 29. While this extra day doesn't mean any increase in your salary, it's still an event on the calendar. In English, this day has a very special name: Leap day. In French, it is “medieval day”.

Why is February 29?

Our calendar doesn't exactly match the reality of the solar system: if the Gregorian calendar has 365 days in a year, it doesn't take 365 days for the Earth to revolve around the Sun. It will take 5 hours, 48 ​​minutes and 56 seconds. This doesn't sound like much on paper, but if we accumulate this difference year by year, our calendar has nothing to do with the seasons at a rate of 24 days difference per century. While July is characterized by freezing temperatures, we celebrate Christmas in spring in the midst of summer heat.

To maintain seasonal consistency, we must “catch” these hours. In fact, the calendar constantly sees an extra day being added. This is what we call a leap year: a year with 366 days instead of 365. But this does not completely solve the problem: where to spend this day? For example, why not make December 32?

This extra day is logically added to February, which is usually the shortest month of the year with 28 days. This cannot happen every year; So a leap year is one whose year is divisible by four. This happens approximately every four years. To make matters more complicated: a year cannot be a leap year if it is a multiple of 100, unless it is a multiple of 400 (conclusion, 2000 is a leap year, not 1900).

But why a “leap”?

Despite this weird calculation, you get the idea: we're talking about a “leap day” in English because we're making a little shortcut to make up for lost hours: leap, in English, not only refers to a tab, but also refers to the concept of a shortcut. In French, we speak of “intermediate day” because February 29 falls in an exceptional way between February 28 and March 1.

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