A punch made of sweetened ale or wine heated with spices and roasted apples; especially at Christmas WordNet 3.0 & Open English WordNet

Wassail is a beverage made from hot mulled cider, ale, or wine and spices, drunk traditionally as an integral part of wassailing, an ancient English Yuletide drinking ritual and salutation either involved in door-to-door charity-giving or used to ensure a good harvest the following year. Wikipedia

The beverage served during a wassail, especially one made of ale or wine flavoured with spices, sugar, roasted apples, etc. Wiktionary

Beverage served during a wassail. Wiktionary (translation)