Ó Dubhlainn
Ó DUBHLAINN—I—O Dowlan, O Dowlin, O Doolen, O'Doolan, Doolan, Doolin, (Dowling), &c.; 'descendant of Dubhfhlann' (black Flann); the name of a family of the Ui Maine, in Co. Galway. Its anglicised forms cannot always be distinguished from those of Ó Dubhláin and Ó Dúnlaing, which see.
Alphabetical Index to Irish Surnames