Months in Irish: Eanáir to Nollaig, festival months and the date

Latin months, festival months and harvest months

The months in Irish fall into four groups. The first is Latin: Eanáir, Feabhra, Márta, Aibreán and Iúil came into Irish from the Roman names, most of them early enough to pass through Old Irish. Wiktionary traces Feabhra to Old Irish Febrae and Aibreán to Old Irish Apréil, with an ending reshaped to the Irish suffix -án.

The second group carries the great festivals of the Gaelic year. Bealtaine, May, is the festival that opened the summer; Lúnasa, August, comes from Lughnasadh, the festival at the start of the harvest; Samhain, November, is the festival at the start of winter. The Wikipedia article on the Irish calendar names all three as months named after Gaelic religious festivals, and the festival and the month still share the word.

The third group describes the farming year. Meán Fómhair is the middle of the harvest and Deireadh Fómhair its end. Meitheamh, June, belongs here too: Wiktionary derives it from Middle Irish mithem, midsummer, and compares Welsh Mehefin and Breton Mezheven.

December stands alone. Nollaig is the Irish word for Christmas, from Latin nātālīcia, a birthday celebration, and the month of December is mí na Nollag, the month of Christmas.

Samhain and mí na Samhna: the genitive after mí

Mí means month. When a month name follows it, the name goes into the genitive, and for most months nothing visible happens. Samhain and Nollaig do change: the month of November is mí na Samhna and the month of December mí na Nollag. Both are feminine nouns, and the feminine article na stands in front of them.

This is the form that shows up in dates written out in words. Foclóir.ie gives an tríú lá de mhí na Samhna, the third of November, literally the third day of the month of November, and tús mhí na Nollag, the beginning of December. In both phrases mí itself is lenited to mhí after de and in the genitive construction.

Wiktionary lists Mí na Nollag as the name of the month and keeps Nollaig for Christmas itself. The table follows foclóir.ie and the site's months of the year table, which give Nollaig as the month name and mí na Nollag as its use after mí.

How to write a date with the months in Irish

In figures an Irish date puts the article before the number and the month after it: an 25 Samhain for 25 November, an 25 Nollaig for Christmas Day. With a weekday the day comes first, as in foclóir.ie's Dé Luain an 10 Iúil, Monday 10 July.

Written out, the number becomes an ordinal and the month moves into the genitive with mí: an tríú lá de mhí na Nollag, the third of December.

Month names are capitalised in Irish, unlike in French or Dutch: Eanáir, Bealtaine, Meán Fómhair. Both words of the two-word months take a capital. The fada belongs to the spelling, so Márta, Aibreán, Iúil and Lúnasa are misspelt without it.

The Irish months among the Celtic languages

Scottish Gaelic and Manx, the two other Goidelic languages, share some of these roots and differ in others. On the site's months table Scottish Gaelic opens the year with Am Faoilleach and Manx with Jerrey Geuree, both native names where Irish uses the Latin Eanáir, while all three have a form of Márta for March. Welsh, a more distant relative, has Ionawr, Chwefror and Mawrth.

The festival names travelled furthest. Samhain is known far outside Ireland through Halloween, which falls on its eve, and Lughnasadh and Beltaine are still used for the festivals in English. In Irish they remain ordinary month names on every calendar.