Irish Family Names D
O'DALY, O'DALLY
NAME ON MAP: O'DALAIGH MODERN COUNTY: Westmeath MEANING: `descendant of Dálach'. (Dál meant `assembly'; the modern Irish word, of course, is dáil.) It was a literary family: Cuconnacht O’Dálaigh was a 12th century poet in Meath; Donagh O'Dálaigh, known as `the Irish Ovid', died in County Clare in 1244; and Muireadhach Albanach O'Dálaigh is remembered for his spirited poetic defence of his action in killing of a tax collector.
O'DEMPSEY
NAME ON MAP: O'DIOMASAIGH MODERN COUNTIES: Leix, Offaly MEANING: `descendant of Díomasach'. (The name meant `proud.') He was one of the few Irish chieftains to better Strongbow on the field of battle.
MacDERMOT, KERMODE
NAME ON MAP: MacDIARMADA MODERN COUNTY: Roscommom MEANING: `son of Diarmaid'. (The name meant `envy free'). There were three separate septs, the most important in Roscommon being descended from Tadhg O'Connor, King of Munster before the Anglo-Norman invasion.
O'DEVLIN
NAME ON MAP: O'DOIBHILIN MODERN COUNTY: Tyrone MEANING: `descendant of Dobh(a)iléin'. (The name possibly derived from dobhail `unlucky'.) There was a Bishop O'Doibhilin of Kells in 1211. An early sept in Sligo had died out by 1300.
DILLON
NAME ON MAP: DYLON MODERN IRISH NAME: Dillon MODERN COUNTY: Westmeath MEANING: Sir Henry de Leon, from Brittany, accompanied the Earl of Morton, later King John of England, to Ireland in 1185 and was granted large estates in West Meath. His son adopted the name Dylon and the family's land became known as Dillon's Country.
O'DOHERTY, MACDEVITT
NAME ON MAP: O'DOCHARTAIGH MODERN IRISH NAME: O' Dochartaigh, MacDaibhaid MODERN COUNTY: Donegal MEANING: `descendants of Dochartach'. (The name meant `obstructive, unlucky'.) The MacDevitt (`son of David') sept came from the same stock, being descended from a David O`Doherty, who was killed in 1208.
MacDONAGH
NAME ON MAP: MacDONNACHADHA MODERN COUNTY: Sligo MEANING: `son of Donnchadh (Donagh)'. (The name derived from don `brown' and cath `battle'.) The sept was a branch of the Connacht MacDermots.
MacDONLEVY, DUNLEAVY, LEAVY
NAME ON MAP: MacDUINNSHLÉIBHE MODERN COUNTY: Donegal MEANING: `son of Duinnshléibh'. (The name derived from donn `brown' and sliabh `mountain'.) Originally the Royal family of Down and South Antrim, the sept migrated to Donegal after being defeated by the Anglo-Norman John de Courcy in 1177. They became the hereditary physicians to the MacDonnells. See the entry for MacNulty.
MacDONNELL
NAME ON MAP: MacDOMHNAILL MODERN COUNTY: Antrim MEANING: `son of Domhnall (Donal)'. (The name derived from dubno `world' and val- `might, rule'.) The most important sept came from Argyll, Scotland, as galloglasses (gall `foreign' óglách `servant, warrior', ie. mercenaries) and were established in the Glens of Antrim by the 14th century. There were two smaller Irish septs in Connacht. (The name Argyle `territory of the Gaels', incidentally, derived from the Irish colonization of Scotland centuries before. See the entry for Carrickfergus.)
O'DONNELL
NAME ON MAP: O'DOMHNAILL MODERN COUNTY: Donegal MEANING: `descendant of Domhnall (Donal)'. Domhnall, died 901, claimed direct descent from Niall of the Nine Hostages. The sept was dominant in the territory of Tyrconnell (modern County Donegal) at the time of this map. See the previous entry.
O'DONNELLY
NAME ON MAP: O'DONNGHAILE MODERN COUNTY: Tyrone MEANING: `descendant of Donnghal'. Donnghal O'Néill was 17th in descent from Niall of the Nine Hostages. (The name derived from donn `brown' and gal `valour.) The sept moved from Donegal to Tyrone before 1300.
O'DONOGHUE, DONOHOE
NAME ON MAP: O'DONNHACHADHA MODERN COUNTY: Cavan MEANING: `descendant of Donnchadh (Donagh)'. See the entry for MacDonagh.
O'DONOVAN
NAME ON MAP: O'DONNABHAIN MODERN COUNTY: Cork MEANING: `descendant of Donndubhán'. (The name came from donn `brown', dubh `black' and the suffix án.) The largest sept was pushed from Limerick into Cork by Anglo-Norman pressure.
O'DOWD, DOODY, DUDDY
NAME ON MAP: O'DUBHDA MODERN COUNTY: Sligo MEANING: `descendant of Dubhda'. (The name came from dubh `black'). The sept descended from Fiachra, brother of Niall of the Nine Hostages.
O'DOYLE
NAME ON MAP: O'DUBHGHAILL MODERN COUNTY: Wexford MEANING: `descendant of Dubhghall'. (The name derived from dubh `dark' and ghall `foreigner'.) The earliest record of the name is as far back as 978; this, plus the fact that the name had a coastal distribution, makes it probable that the `dark foreigner' was a Viking.
O'DRISCOLL
NAME ON MAP: O'hEIDERSCEOIL MODERN IRISH NAME: O'Drisceoil MODERN COUNTY: Cork MEANING: The original name was O'hEidersceoil: `the descendant of Eidhersceoil'. (The name meant `messenger.') He was a 10th century descendant of Lughaidh Laidhe. The sept had moved from Co. Kerry to Co. Cork by 1300.
O'DUFFY, DOWEY
NAME ON MAP: O'DUBHTHAIGH MODERN COUNTY: Roscommon MEANING: `descendant of Dubhthach'. (The name derived from dubh `black'.) There were septs in Co. Donegal and Co. Monaghan, but in the 14th century the most important was in Roscommon. Muiredagh and Cele O' Dubhthaigh were both Archbishops of Tuam during the 12th century.
O'DUNN
NAME ON MAP: O'DUINN (in a 12th century record) MODERN IRISH NAME: O'Doinn, O'Duinn MODERN COUNTY: Leix MEANING: `the descendant of Donn'. (The name meant `brown, dark'). Gillananaomh O'Duinn, 1102-1160, was a renowned poet and historian.