The holiday and festival days celebrating Whit Sunday or *Pente-cost. Parishes celebrated with games and much *scot-ale. The word is OldEngl. Hwita Sunnandasg, i.e. White Sunday. The first component 'Whit' (white) comes from the custom of the newly baptised wearing white robes; '-sun' is an abbr. of 'Sunday'. -
Dictionary of Medieval Terms and Phrases. Christopher Coredon with Ann Williams.