Olddude,
Don't listen to 'em. The term originated in Somerset in the 19th century. An antiquarian from London was standing on a clifftop in Somerset with a local deaf farmer one New Year. They were looking down on a village where some of the locals were pruning apple trees with shotguns. The Antiquarian asks the farmer 'What's going on down there?' A sailing ship just happened to be going by and the farmer not hearing the question asked 'Wassail is that?'

I'll get me coat!