Ó Dubhláin
Ó DUBHLÁIN—I—O Doelane, O Dowlane, O Dolane, O'Doolan, Doolan, Dolan, (Dowling, Delaney, Delany); 'descendant of Dubhshlán' (black defiance, challenge); a rather common surname in all parts of Ireland, but its anglicised forms cannot always be distinguished from those of Ó Dubhlainn and Ó Dunlaing, which see. Felix O Dubhlain was Bishop of Ossory at the beginning of the 13th century.
Alphabetical Index to Irish Surnames