the first day after Christmas Day that is not a Sunday. Boxing Day is an official holiday in Britain and some other countries. Culture Boxing Day is a bank holiday. Traditionally it was the day when people gave Christmas boxes (small gifts of money) to their employees or servants. Now most people relax, digest the food and drink of the day before, and perhaps visit friends or relatives. Word Origin mid 19th cent.: from the custom of giving tradespeople a Christmas box on this day.