I was recently reading a book written in Corca Dhuibhne Irish by Tomás Ó Conchubhair, called Mo Thinteán Féin. The thing that got me thinking was the very first line of the book:

Usages of words like b'ṡin, b'ṡeo, and b'ṡiúd are found consistently throughout this book. I always thought that this use of copular forms being prefixed by b' was a particularly Cois Fhairrge feature, but I have also found one example of this being used in Labharfad le Cách (though there are probably others):


Along the lines of this I was also curious about the usage of seod instead of seo before é, í, íad. I theorize that both of these copular forms are more common in the Northern dialects of Corca Dhuibhne, as they appear to be less common in the works of Peig Sayers and Tomás Ó Criomhthain, as far as I have been able to tell.

Any help or comment is deeply appreciated, I hope you all are having a good week!

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

In "An tOileánnach", they are quite common, e.g. B’ eo amach na fir ghorma.
And in Muscraí they are used, too, e.g. Peadar Ua Laoghaire: b’ in iad na sagairt ag cabhrú leis an éagóir sin.
Spelling differs, b’shin / b’ in / dob in etc.

Seod is rather sid in Munster and often combined with the pronoun: sidé etc.

I’ve read recently here somewhere that these forms are common in Northern CD but not in the South. To my surprise. I thought they are used in all of Munster.

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

Back to sid: In Gaeilge Chorca Dhuibhne there is no mention of subdialect differences regarding sid.

-eanns in Munster?
There is a non-relative second person singular form in questions (an dtuigeas tú?) – so perhaps even an dtuigeans tú? – but not as a relative form, I’d think.

Only relative forms mentioned in GChD: a bhaineas lé and a leanas

B'shin, b'sheo and b'shiúd are all found in the Irish of Amhlaoibh Ó Loingsigh. I think sin and b'shin are more common than things like nách shin. But i've just found "Nách shidé anso é?" in AÓL's Irish.

an dtuigeas tú has nothing to do with the relative though (I know you didn’t say it has). I believe it’s just due to a sporadic sound change /əntV/ > /əstV/ present in Kerry, so an dtuigeann tú > an dtuigean tú (loss of distinct fortis n in Munster) > an dtuigeas tú treated as a unit.

Compare laethasta, uaireasta in some speakers in place of laethanta, uaireanta, see. pp. 89, 393 in Gaeilge Chorca Dhuibhne.

(Of course the original relative ending -(e)as existed in Munster at some point, but it’s not productive there for a long time, I don’t think -anns has ever been a thing in Munster dialects.)