From Longman Dictionary of Contemporary EnglishMay DayˈMay Day noun [countable, uncountable] TMCSSOthe first day of May, when left-wing political parties in some countries celebrate, and when people traditionally celebrate the arrival of spring
Examples from the Corpus
May Day• Sadly, the question is about May day.• Clun has reinvented its old May Day festival and reinvented the Green Man along with it.• Today is Beltane, the May day festival devoted to the goddess.• He has blamed the police for causing the May Day riot, siding with the Front.• This will take place over the May Day holiday weekend, and there is a choice of travel by air or coach. 