What is a wassail bowl?

Wassail is a mixed drink, sort of like a punch, that traditionally contains some alcoholic beverage as one of the ingredients. The bowl in which it is served is called a wassail bowl. The history of wassail reaches back to at least the 1500s, and wassail bowls in that time period were usually made of wood that had been turned on a lathe to make the bowl form.

From Encyclopædia Britannica: vessel generally made of wood and often mounted in silver, used on ceremonial occasions for drinking toasts. The Word wassail derives from Old Norse ves heill,meaning "be well, and in good health." The name has come to be generally applied to any bowl from which a toast is drunk, as well as to the actual drink itself.