For other uses of similar terms see Sylvester The term silvester (alternately spelled sylvester or sylwester) is used in certain countries (such as Germany, Austria, Poland and Israel) for December 31st in the Gregorian calendar, New Year's Eve. Swedes don't generally refer to the day itself with this name, but traditionally celebrate Silvester on this day as one of its 365 name days, using that spelling as it's the most common spelling of the name in Sweden. The naming refers to Pope Sylvester I, who died on that date in 335.
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