wassailer
noun [ C ]
UK/ˈwɒs.eɪ.lər/ US/ˈwɑː.səl.ɚ/
Notably in the past, a person who takes part in the activity of going from house to house at Christmas time singing carols and traditionally drinking wassail ( warm beer or wine with added spices.)
When alcohol was involved, wassailers often got too rowdy.