Why It Is Called “Leap Day” & “Leap Year” — February 29, 2016.
The ‘Leap’, as in tomorrow’s February 29 “Leap Day“, refers to the fact that on Leap Years a given day LEAPS over one day of the week to break the nice, year-to-year sequence we have in Non-Leap Years.
So pick any date. I chose Christmas BUT any date works (other than Feb. 29 (of course). See the pattern in non-Leap Years. If Christmas fell on a Friday one year, and the next year was NOT a Leap Year, Christmas would fall on Saturday. That is true for all dates. BUT if it is a Leap Year, rather than falling on Saturday it will fall on Sunday (as will be the case this year). Christmas Date LEAPED over Saturday. Hence the ‘Leap’.
This concept of ‘Leap’ is not used in all cultures and languages. Some prefer the more technical intercalary year (year with ‘interposed’ or ‘inserted’ day) or a bissextile year (having to do with the old Roman practice known of “twice sixth”).
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