>> Is úar fri cloï ngaeithe
>> do neoch in-gair Bú Aífe.
> Our phrase is quoted at DIL A 397.65 in the entry for the verb
> “ar-gair...forbids, hinders, prevents...Extended applications....
> is cumma argaire(d) cac mboin ‘equally he would herd every cow’.
> So maybe ‘argair’ is a relative present indicative here. This
> would explain the accusative plural ‘bú’.
Our phrase is also quoted s.v. "in·gair" = herds in DIL.