May 's the fifth month of the year in the Gregorian Calendar and one of seven Gregorian months with the length of 31 days. It's also a month within the northern season of spring. The month May has been named for the Greek goddess Maia, who was identified with the Roman era goddess of fertility, Bona Dea, whose festival was held in May. In both common Western calendrical systems, no other month begins on the same day of the week as May. This month and June are the only two months that've this. (… (More on May)