Ó Dúnlaing
Ó DÚNLAING, Ó DUNLAING—I—O Dowling, O Doolin, Dowling, Dowlin, Dooling, Doolin, Doolen, Doolan, &c.; 'descendant of Dunlang' (an ancient personal name, also written Dúnlang; the name (1) of a numerous family in Leinster, who were at one time lords of Leix; and (2) of a family of Corca Laoighdhe, in South-west Cork, still numerous in Cork and Kerry. This surname is pronounced Ó Dúllaing, and its anglicised forms can hardly be distinguished from those of Ó Dubhlainn, which see.
Alphabetical Index to Irish Surnames