May is the fifth month of the year in the Julian and Gregorian calendars and the third of seven months to have a length of 31 days.
May is a month of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. Therefore, May in the Southern Hemisphere is the seasonal equivalent of November in the Northern Hemisphere and vice versa. Late May typically marks the start of the summer vacation season in the United States and Canada that ends on Labor Day, the first Monday of September.
The month of May (in Latin, Maius) was named for the Greek Goddess Maia, who was identified with the Roman era goddess of fertility, Bona Dea, whose festival was held in May. Conversely, the Roman poet Ovid provides a second etymology, in which he says that the month of May is named for the maiores, Latin for "elders," and that the following month (June) is named for the iuniores, or "young people" (Fasti VI.88).
Mayovka, in the context of the late Russian Empire, was a picnic in the countryside or in a park in the early days of May, hence the name. Eventually, "mayovka" (specifically, "proletarian mayovka") came to mean an illegal celebration of May 1 by revolutionary public, typically presented as an innocent picnic.
Special devotions to the Virgin Mary take place in May. See May devotions to the Blessed Virgin Mary.
Eta Aquariids meteor shower appears in May. It is visible from about April 21 to about May 20 each year with peak activity on or around May 6. The Arietids shower from May 22 - July 2, and peaks on June 7. The Virginids also shower at various dates in May.
Ancient Roman observances
Under the calendar of ancient Rome, the festival of Bona Dea fell on May 1, Argei fell on May 14 or May 15, Agonalia fell on May 21, and Ambarvalia on May 29. Floralia was held April 27 during the Republican era, or April 28 on the Julian calendar, and lasted until May 3. Lemuria (festival) fell on 9,11, and 13 May under the Julian calendar. The College of Aesculapius and Hygia celebrated two festivals of Rosalia (festival), one on May 11 and one on May 22. Rosalia was also celebrated at Pergamon on May 24-26. A military Rosalia festival, Rosaliae signorum, also occurred on May 31. Ludi Fabarici was celebrated on May 29 - June 1. Mercury would receive a sacrifice on the Ides of May (May 15). Tubilustrium took place on May 23 as well as in March. These dates do not correspond to the modern Gregorian calendar.
- May's birthstone is the emerald which is emblematic of love and success.
- The May birth flowers are the Lily of the Valley and the Crataegus monogyna. Both are native throughout the cool temperate Northern Hemisphere in Asia, Europe, and in the southern Appalachian Mountains in the United States, but have been naturalized throughout the temperate climactic world.
- The "Mayflower" Epigaea repens is a North American harbinger of May, and the floral emblem of both Nova Scotia and Massachusetts. Its native range extends from Newfoundland south to Florida, west to Kentucky in the southern range, and to Northwest Territories in the north.
- The zodiac signs for the month of May are Taurus (until May 20) and Gemini (May 21 onwards).
Non-Gregorian observances, 2019
(All Baha'i, Islamic, and Jewish observances begin at the sundown prior to the date listed, and end at sundown of the date in question unless otherwise noted.)
Movable observances, 2019
Sunday after Divine Mercy Sunday: May 5
Monday and Tuesday in the week following the third Sunday of Easter: May 6-7
Fourth Sunday after Easter: May 12
Fourth Friday after Easter: May 17
Third Sunday of May: May 19
Sunday preceding the Rogation days: May 26
Monday, Tuesday, and Wednesday preceding Feast of the Ascension: May 27-29
39 days after Easter: May 30
Wednesday after Pascha: May 1
Thursday after Pascha: May 2
Friday after Pascha: May 3
Saturday after Pascha: May 4
8th day after Pascha: May 5
2nd Tuesday of Pascha, or 2nd Monday of Pascha, depending on region: May 6 or May 7
2nd Sunday following Pascha: May 12
4th Sunday of Pascha: May 26
Wednesday after the Sunday of the Paralytic: May 29
Last Friday in April to the first Sunday in May: April 26 - May 5
First Thursday: May 2
First Saturday: May 4
First Sunday: May 5
First full week: May 5-11
Tuesday of First full week: May 7
Wednesday of first full week: May 8
Second week in May: May 5-11
First Tuesday: May 7
Friday preceding Second Sunday in May: May 10
Saturday closest to May 10: May 11
Second Saturday: May 11
Second Weekend: May 11-12
Second Sunday: May 12
- National Nursing Home Week (United States)
- Children's Day (Spain)
- Father's Day (Romania)
- Mother's Day (Anguilla, Aruba, Australia, Austria, Bahamas, Barbados, Bangladesh, Belgium, Belize, Bermuda, Bonaire, Brazil, Brunei, Canada, Chile, Colombia, Cuba, Croatia, Curaçao, Czech Republic, Denmark, Ecuador, Estonia, Finland, Germany, Greece, Grenada, Honduras, Hong Kong, Iceland, India, Italy, Jamaica, Japan, Latvia, Malta, Malaysia, the Netherlands, New Zealand, Pakistan, Peru, Philippines, Puerto Rico, Singapore, Slovakia, South Africa, Suriname, Switzerland, Taiwan, Trinidad and Tobago, Turkey, United States, Uruguay, Venezuela, Zimbabwe)
- State Flag and State Emblem Day (Belarus)
- World Fair Trade Day
Week of May 12: May 12-18
Third Weekend, including Friday: May 17-19
Third Friday: May 17
Third Saturday: May 18
Third Sunday: May 19
Monday on or before May 24: May 20
Third Monday: May 20
Monday on or before May 25: May 20
Last Monday preceding May 25: May 20
May 24, or the nearest weekday if May 24 falls on a weekend: May 24
Saturday closest to May 30: May 25
Last Weekend: May 25-26
Last Sunday: May 26
Last Monday: May 27
Last Wednesday: May 29
Last Thursday: May 30
Fixed observances in May
- April 29 to May 5 in Japan, which includes four different holidays, is called "Golden Week". Many workers have up to 10 days off. There is also 'May sickness', where new students or workers start to be tired of their new routine. (In Japan the school year and fiscal year start on April 1.)
- May 1
- May 2
- May 3
- May 4
- May 5
- May 6
- May 7
- May 8
- May 9
- Anniversary of Dianetics (Church of Scientology)
- Europe Day (European Union)
- Liberation Day (Guernsey), commemorating the end of the German occupation of the Channel Islands during World War II.
- Liberation Day (Jersey), commemorating the end of the German occupation of the Channel Islands during World War II.
- Time of Remembrance and Reconciliation for Those Who Lost Their Lives during the Second World War, continued from May 8.
- Victory Day observances, celebration of the Soviet Union victory over Nazi Germany (Soviet Union, Azerbaijan, Belarus, Bosnia and Herzegovina, Georgia, Israel, Kazakhstan, Kyrgyzstan, Moldova, Russia, Serbia, Tajikistan, Turkmenistan, Uzbekistan)
- Victory Day over Nazism in World War II (Ukraine)
- Victory and Peace Day (Armenia) marks both the capture of Shusha (1992) in the Nagorno-Karabakh War, and the end of World War II.
- May 10
- May 11
- May 12
- May 13
- May 14
- May 15
- May 16
- May 17
- May 18
- May 19
- May 20
- May 21
- May 22
- May 23
- May 24
- May 25
- May 26
- May 27
- May 28
- May 29
- May 30
- May 31