Mac Dúnadhaigh
Mac DÚNADHAIGH—IV—M'Dowany, M'Downey, M'Doney Dooney, Downey, Doney; 'son of Dúnadhach' (derivative of Dúnadh, of the dún or fort); the name of an old Galway family who are probably a branch of the O'Maddens. Also called Ó Dúnadhaigh, which see.
Alphabetical Index to Irish Surnames