Goib(h)niu isn't Modern Irish which is Gaibhne, gen. Gaibhneann
Brian mac Gaibhneann



There's Aodhnait, Odharnait, Earnait, and others with -nait.
But none of them is pronounced AYSH-

That spelling wouldn’t be used today. As in, it’s just not a Modern Irish form. It’s Old Irish, the pronunciation being (using simplified IPA, Celticist notation) /ɡov´n´u/, and the Old Irish genitive would be Goibnenn /ɡov´n´əN/. But it’s not Modern Irish.

Modern Irish Gaibhne and Gaibhneann (/ɡav´n´ɪ, ɡav´n´əN/?) (or Goibhne, Goibhneann, not sure, /ɡov´n´ɪ/? /ɡev´n´ɪ/?) are direct regular outcomes of those old forms, compare Old Irish Ériu, Érenn → modern Éire, Éireann.

If the old spelling were used today it’d perhaps then be treated like a foreign name (so kept unlenited, not changing according to cases), cause it just doesn’t work in Modern Irish. Kinda like Þunor would not be used today in English (you’d rather use Thor borrowed from the Norse, since the native name was lost) or like you would not write Wǣringwīċsċīr in a modern English text but rather Warwickshire, or Ēadmūnd vs Edmund, or Portesmūþa vs Portsmouth, etc.


/nət´ ~ nɪt´/, that is, with the vowel of English about or maybe kit (a centralized vowel, said with mouth and tongue relaxed) and Irish slender /t´/, sound that does not exist in English (but, depending on dialect, something similar to Russian “soft” ть or Czech ť, or English ch).

You can try entering the names into https://abair.ie/en/ – it’ll give you some idea how they would be pronounced in three main dialectal areas (but bear in mind, the sound synthesis is not perfect).

In modern Munster Irish the name is said as if spelt "Goínge" with genitive "Goíngean".

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The dialect I use is Cork Irish.
Ar sgáth a chéile a mhairid na daoine, lag agus láidir, uasal is íseal

That is, /ɡiːŋ´ɪ/ or /ɡəiŋ´ɪ/? And that’s Cork, right? with Kerry being as if Goíne /ɡiːn´ɪ/ then?

The first one /ɡiːŋ´ɪ/.
I've heard it in Cork and Kerry, but for a name so unusual it could be /ɡiːn´ɪ/ as well and I might not have heard it.

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The dialect I use is Cork Irish.
Ar sgáth a chéile a mhairid na daoine, lag agus láidir, uasal is íseal