Wikipedia tells us the following (among other things) on what teachers and pupils in Bavaria are about to begin (s.v. Holiday):

Etymology

Holiday

Holiday is a contraction of holy and day, holidays originally represented special religious days. This word has evolved in general usage to mean any special day of rest (as opposed to regular days of rest such as the weekend).

Vacation

In the United Kingdom the word “vacation” referred specifically to the long summer break taken by the law courts (and later universities)—a custom introduced by William the Conqueror from Normandy where it was intended to …

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