Short for Wapatui. Midwestern United States slang for punch served in a bucket at college parties that contains kool-aid, fruit and several bottles of the most vile and cheap hard liqour available. Preffered by underagers who haven't learned to like beer, but is deadly stuff.
In other parts of the States this is known as Jungle Juice
I went to that WAP party last night, and I can't stop vomiting now.