Go raibh míle maith agat, a Labhráis!
That brings another question, though. What was that 'rejoicing' associated with? Was it some Christian or pre-Christian holiday?

Níl a fhios agam.

Ach foinse eile, MacBain's dictionary:
http://www.ceantar.org/Dicts/MB2/mb17.html


agus



http://www.teanglann.ie/en/fgb/faoilidh:

http://www.teanglann.ie/en/fgb/fáilí

Seo é an nasc a bhí i gceist agat, measaim, a Labhráis. http://www.teanglann.ie/en/fgb/f%C3%A1il%C3%AD

Thank you this is helpful. But I noticed that some of the months use na, and one uses 'n, and the others use nothing. Is there any rhyme or reason to this?

Then, are there any circumstances in which you would use the name of the month on its own without Mhí/Mí in front of it? For example, are there any contexts in which you refer to November as "Samhna" or "Samhain" rather than Mí na Samhna, or refer to August as Lunasa rather than "M(h)í Lúnasna"?

I am trying to learn about dates and months with Duolingo. It is picky about these aspects but does not offer much in the way of explanation!

I think nowadays anyhow when writing the date, on a letter for example, you'd write that short form, or even 15/4/2018 (remember in Ireland we put the day first, then the month.).

Notice if you're using Mí before the month it changes to genitive, but nominative in the short form.

Bealtaine, Samhain, and Lúnasa were ancient festivals, the months are named after those.
Samhain - is also the modern day Halloween.

na is the word 'the' before a feminine noun in this context
an or 'n is the word 'the' before a masculine noun in this context

then nothing before a proper month name (Eanáir, Aibreán, Lúnasa) -- we do not refer to "The January" but merely "January"
and also nothing before compound nouns (Meán Fómhair, Deireadh Fómhair)

So yes, actually, they are all regular and predictable assuming, of course, that you know all the words, their genders, and the grammar rules.



Except for the three mentioned above (Eanáir, Aibreán, Lúnasa), none of the words after Mí are the names of months. For example, as Bríd pointed out, Mí na Samhna means the month of Halloween. Mí na Súl Buí, which is not the official standard Irish name for July, means literally the month of the yellow eyes or the month of the corn marigolds. If you just spoke about "the yellow eyes" or "the corn marigolds" then no one would have any idea you were referring to a month at all! And if you spoke of Samhain alone, then you would be discussing the feast, not the month.

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ЯГОН ТОҶИК НЕСТ ИНҶО???

And, because they are in genitive, I would translate them as ‘of the’. ;-) (‘the’ in nominative singular is always an, never na, and causes different mutations)