From: Old-Irish-L <[log in to unmask]> On Behalf Of Dennis King
> Is dócha, faoin am seo, go bhfuil tú tar éis súil a chaitheamh ar chuile fhocal dár chríoch -thir. Mar sin féin …
> What do you make of the ending of “crithir” as derived from “crith” or otherwise?
The problem is that what in OIr. looks synchronically like a uniform suffix -thir can have a multitude of origins. Each word has to be analysed on its own terms. In the Milan Glosses database, Aaron Griffith analysed crithir as an i-stem with question mark. This is probably the most straightforward analysis given what is attested, but other analyses would also be possible. The attestations of beithir are of a different nature, though, so the analysis of the one cannot be simply transferred unto the other.