Words and Proper Names

Áth Fir Diad

10826.
Ó Flaithearta (Mícheál): The etymologies of (Fer) Diad.
In Ulidia 2 (2009), pp. 218–225.
Suggests diad in personal name (Fer) Diad derives from gen. *dwi-pod-os of PIE *dwi-pod-s ‘two-footed’.