Boxing Day

Harry Potter4里出现的，想来是一个比较传统的节日，一查果然

Boxing Day
Boxing Day is the day after Christmas, a public holiday in most countries in The Commonwealth. It originated as a day for giving gifts to employees and poor people. It has sporting traditions, especially fox hunting and the famous boxing day round in the English Premier League, and is the day when stores launch the most significant sales period in the retail cycle.

It is usually celebrated on 26 December, the day after Christmas Day;, but can move to 27 December or 28 December if 26 December is a Saturday or Sunday. The movement of Boxing Day varies between countries.

The public holiday is recognised in the United Kingdom, Canada, New Zealand and Australia, as well as many other members of the Commonwealth of Nations.

Origins
Boxing Day is a traditional celebration dating back to the Middle Ages, of which the primary practice is the giving of gifts to employees or to people in a lower social class. The name has numerous folk etymologies.