Patricia Kelly has mentioned the various words used for fox in her article on dialect in Old Irish. I don't have it to hand but I know it is one of the words she suggesrts may represent dialectal variation during the Old Irish period...
Kelly, P. (1982) 'Dialekte im Altirischen?' in Sprachwissenschaft in Innsbruck. , (Wolfgang Meid, Hermann Ölberg and Hans Schmeja eds), Innsbruck, *.
--- On Fri, 9/4/10, David Stifter <[log in to unmask]> wrote:
From: David Stifter <[log in to unmask]>
Subject: Re: [OLD-IRISH-L] crimthann
To: [log in to unmask]
Date: Friday, 9 April, 2010, 10:31
On Fr, 9.04.2010, 04:57, Helen McKay wrote:
> In the highlands I have also heard that they use another form - red dog
> (madra). Seems like we are supposed to use any other word than the 'real'
> one - whatever that is?
The inherited word is "loarn", which seems to appear once, and which is
also attested as a personal name. It derives from Proto-Celtic *loferno-,
just like British *lowarn, Gaul. Louernios.