A dhaoine uaisle,

I've been a learner of Irish Gaelic for over thirty years. I've always accepted that there are three main dialects (Gaedhilg, Gaeilge, Gaelainn) and An Caighdeán Oifigiúil.

Thanks to Duolingo, I've recently begun to add Scottish Gaelic to my repertoire. In the course of learning Scottish Gaelic I noticed that the Scottish Gaelic dictionaries do not have a head word akin to Irish Gaelic caighdeán.

So, I checked older Irish Gaelic dictionaries (O'Reilly's and Dinneen's) and found that they also do not include caighdeán as a headword.

My primary question is, does anyone know the etymology of caighdeán?

Another, perhaps rhetorical, question is, why was the dialect name Gaeilge re-used as the name for An Caighdeán Oifigiúil?

-gma

I don’t know the etymology, but the second edition of Dinneen’s dictionary (1927) does have it (you can view it here or here):

Interesting. I was looking at the 1904 edition of Dinneen's Dictionary which does not include caighdeán.

Is caighdeán a neologism of the 1920s? Perhaps it's a gaelicized version of the Greek word κανών (canon) which also means standard.

I don’t see how or why Greek κανών would change to caighdeán with /d´/ in it, and written with gh… It doesn’t really look like the Greek word. Also, I don’t see why people in the 1920s would want to give their newly created neologism the meaning of ‘the measured distance between the knots of the hanging thread on the rope of a fishing net’ – that’s pretty specific.

But also I can’t quickly find anything older about the word, there’s nothing in the leamh.org glossary and dil.ie doesn’t find anything for caigd*, caighd*, cagd*, nor caghd*, so no idea.

Well, thanks for trying! I'll post the question to the Irish History Reddit.

I don't know but if it is a measured (und obviously highly standardized) distance I'd suppose it could be related to the number fifty (in whatsoever measurement) - Old Irish óic, Modern Irish aog changed to a weak aigh, -d- because caoga is an nt-stem (caogad), án as a suffix.

It appears the caighdeán was a Munster Dialect that entered the broader lexicon in 1992 via this book:

Réilthíní Óir

Cuid a 1 Mac CLúin

An t-ath. Seóirse Mac Clúin,

Ollamh le Gaoluinn,

Coláiste Fhlannáin, Inis, Co. an Cláir

1922

...

Caighdeán--nó caidhdeán==faid dhá mhogal de líon==

marc, tomhas, comhartha. Indiu Lá an chaighdeán ag Dáil

Éireann==an marc-Lá, an sprioc-Lá, an Lá ar a raibh

ceapaithe aca teacht le cheile. Níl aon chaighdeán fós leis

an Lá go bhfuighmíd cúntas==marc, níl aon rud a déarfadh

linn cad é an Lá. Tá caighdeán eile le cruinniú na n-Óglaoch

==téarma, tomhas.

There is no evidence that caighdeán was a Munster dialect word that only entered the wider lexicon in 1922 via Réilthíní Óir. You can't just make such statements up. The evidence of Réilthíní Óir is that this word was used in the fishing trade: it was a measurement for a length of fishing net. As such, you would not expect it to have been used frequently in print. To state definitely that it was not used ever in Connaught or Ulster -- well, you would need to prove a negative, and have a knowledge of fishing-net terms from those provinces. You might be on to firmer ground if you were to argue that caighdeán was likely to have been in use in fishing for a long time, and then its meaning of "measurement" was extended to the phrase "is maith an caighdeán an fhírinne", and then in the modern day the meaning was extended again to "a standard language". But there is zero evidence that before 1922 caighdeán in the fishing-net meaning was confined to Munster.

Read Father McClune's foreword. If you want to contradict him, find an earlier non-Munster Dialect record of caighdeán.

There was a review in "The Irish Monthly" journal of Réilthíní Óir (Cuid a haon) noting that the book is a collection of words from the Clare and Kerry dialects:
L. McK. The Irish Monthly 50, no. 589 (1922): 301–301. http://www.jstor.org/stable/20505888.