Names with the Prefix O

Robert E. Matheson
1909
Chapter IV | Start of chapter

Name.

County.

O’Ahern,

Cork.

O’Baire,

Cork.

O’Bannan,

King’s, Mayo.

O’Begley,

Cork, Donegal.

O’Behan,

King’s.

O’Beirne,

Roscommon.

O’Billry,

Limerick.

O’Birn,

Mayo.

O’Bligh,

Mayo.

O’Bolger,

Carlow, Kilkenny.

O’Boylan,

Monaghan.

O’Boyle,

Donegal.

O’Bradley,

Cork, Donegal.

O’Branagan,

Louth.

O’Bree,

Kilkenny.

O’Brennan,

Kerry, Kilkenny.

O’Breslin,

Donegal, Fermanagh, Tipperary.

O’Bric,

Waterford.

O’Brien,

Clare, Cork, Limerick, Tipperary, Waterford.

O’Brien or Mac-I-Brien.

Tipperary.

O’Brigan,

Cork.

O’Brodar,

Donegal, Kilkenny.

O’Brody,

Mayo.

O’Brogan,

Cavan, Mayo, Queen’s, Sligo.

O’Brolchan,

Londonderry.

O’Brosnaghan,

Kerry.

O’Byrne,

Wicklow.

O’Cahaney,

Mayo.

O’Cahill,

Carlow, Clare, Galway, Kerry, Tipperary.

O’Callaghan,

Clare, Cork, Mayo. Tipperary.

O’Callan,

Armagh, Kilkenny

O’Callanan,

Cork, Galway.

O’Canavan,

Galway.

O’Cannanan,

Donegal.

O’Carberry,

Westmeath.

O’Carey,

Kildare.

O’Carmody,

Clare.

O’Carolan,

Londonderry, Meath.

O’Carragher,

Louth.

O’Carroll,

Kerry, Kilkenny, King’s, Leitrim, Louth, Tipperary.

O’Casey,

Cork, Fermanagh, Kerry, Limerick, Westmeath.

O’Cashin,

Galway.

O’Cassidy,

Fermanagh, Londonderry, Monaghan.

O’Cavanagh,

Carlow, Wexford.

O’Cawley,

Galway.

O’Claisin,

Cork.

O’Clerkin,

Limerick.

O’Clery,

Cavan, Clare, Donegal, Galway.

O’Coffey,

Galway, Westmeath.

O’Coigley,

Donegal, Fermanagh.

O’Coleman,

Cork, Louth, Sligo.

O’Colgan,

Armagh, Down, Kildare.

O’Colman,

Louth.

O’Coltaran,

Down.

O’Conaghty,

Cavan, Sligo.

O’Concannon,

Roscommon.

O’Conealy,

Galway.

O’Conlan,

Limerick.

O’Connegan,

Mayo.

O’Connelan,

Tyrone.

O’Connell,

Clare, Down, Galway, Kerry, Limerick.

O’Connellan,

Galway, Mayo, Roscommon.

O’Connolly,

Galway, Monaghan.

O’Connor,

Kildare, Roscommon.

O’Conolly,

Meath.

O’Conor,

Clare, Galway, Kerry, King’s, Londonderry, Mayo, Roscommon, Sligo.

O’Conran,

Waterford.

O’Considine,

Clare.

O’Cooney,

Tyrone.

O’Corcoran,

Fermanagh, Tipperary.

O’Corley,

Sligo.

O’Cormac,

Down.

O’Corr,

Roscommon.

O’Corran,

Tyrone.

O’Corrigan,

Fermanagh, Westmeath.

O’Cosgry,

Wexford.

O’Cowhy,

Cork.

O’Coyle,

Cavan, Donegal.

O’Creagh,

Clare, Cork, Kerry.

O’Crean,

Sligo.

O’Criocan,

Tyrone.

O’Criodan,

Antrim.

O’Cronin,

Kerry.

O’Cronly,

Cork.

O’Crossan,

Tyrone.

O’Crotty,

Waterford.

O’Crowly,

Cork.

O’Cuire,

Tipperary.

O’Cuirneen,

Leitrim.

O’Cullen,

Cork, Galway, Kildare, Limerick, Tipperary, Wicklow.

O’Cullenan,

Clare, Cork, Tipperary.

O’Culligan,

Clare.

O’Cummin,

Mayo.

O’Curran,

Clare, Donegal.

O’Curry,

Cavan, Cork, Westmeath.

O’Daly,

Cavan, Clare, Cork, Galway, Kerry, Westmeath.

O’Danaher,

Cork.

O’Davoren,

Clare.

O’Dea,

Clare, Cork, Tipperary.

O’Deasey,

Cork.

O’Deegan,

Clare.

O’Delany,

Kerry, Kilkenny.

O’Dempsey,

Kildare, King’s, Queen’s.

O’Dennehy,

Waterford.

O’Dennery,

Cork.

O’Dermody,

Clare, Tipperary.

O’Devin,

Fermanagh.

O’Devir,

Donegal.

O’Devlin,

Londonderry, Sligo

O’Dinan,

Tipperary.

O’Dinane,

Cork.

O’Dineen,

Cork.

O’Dinerty,

Tipperary.

O’Dinnahan,

Limerick.

O’Dogherty,

Donegal, Mayo.

O’Dolan,

Cavan, Mayo.

O’Donaghey,

Galway.

O’Donegan,

Cork.

O’Donelly,

Donegal.

O’Donevan,

Limerick.

O’Donlevy,

Donegal, Down, Tyrone.

O’Donnegan,

Armagh, Fermanagh, Tipperary, Tyrone.

O’Donnelan,

Roscommon.

O’Donnell,

Donegal, Galway, Mayo, Sligo.

O’Donnellan,

Antrim, Galway.

O’Donnelly,

Tipperary, Tyrone.

O’Donoghoe,

Kerry, Kilkenny.

O’Donohoe,

Tipperary.

O’Donovan,

Cork, Limerick.

O’Dooley,

Westmeath.

O’Doolin,

Kerry.

O’Dooyarma,

Donegal.

O’Doran,

Queen’s, Wexford.

O’Dorchy,

Mayo.

O’Dornin,

Donegal.

O’Dorrian,

Donegal.

O’Dowd,

Mayo, Sligo.

O’Dowling,

Queen’s, Wicklow.

O’Doyle,

Carlow, Galway, Kilkenny, Wexford, Wicklow.

O’Doyne,

Carlow.

O’Dreenan,

Galway.

O’Drinan,

Clare.

O’Driscoll,

Cork.

O’Drom,

Cavan.

O’Duane,

Galway.

O’Duff,

Queen’s.

O’Duffy,

Donegal, Galway, Mayo, Monaghan.

O’Dugan,

Cork, Mayo, Roscommon, Wexford.

O’Duigenan,

Roscommon.

O’Dunn,

Kildare, Meath, Queen’s.

O’Dunnady,

Kerry.

O’Durkan,

Sligo.

O’Duvan,

Meath.

O’Duvany,

Armagh, Tyrone.

O’Dwyer,

Tipperary.

O’Eire,

Antrim.

O’Etigan,

Tyrone.

O’Fahy,

Galway.

O’Fallon,

Roscommon.

O’Falvey,

Cork, Kerry.

O’Farrelly,

Cavan.

O’Fay,

Westmeath.

O’Feenaghty,

Kerry, Roscommon.

O’Feeney,

Galway, Sligo.

O’Felan,

Fermanagh, Waterford.

O’Ferral,

Longford.

O’Fihelly,

Cork, Roscommon.

O’Finan,

Mayo.

O’Finegan,

Mayo, Roscommon.

O’Finn,

Leitrim.

O’Finnelan,

Westmeath.

O’Flahavan,

Waterford.

O’Flaherty,

Galway.

O’Flanagan,

Fermanagh.

O’Flannagan,

Roscommon, Waterford.

O’Flannelly,

Sligo.

O’Flannery,

Limerick, Mayo.

O’Flattery,

Clare.

O’Florry,

Down.

O’Flynn,

Antrim, Cork, Kerry, Mayo, Roscommon.

O’Fogarty,

Tipperary.

O’Foley,

Kerry.

O’Foran,

Galway.

O’Forranan,

Donegal.

O’Fox,

Longford, Meath.

O’Freel,

Donegal, Londonderry.

O’Furey,

Tipperary.

O’Furry,

Antrim.

O’Fynn,

Clare.

O’Gahan,

Wicklow.

O’Gallagher,

Donegal.

O’Gallivan,

Kerry.

O’Gara,

Sligo.

O’Garvey,

Armagh, Down, Wexford.

O’Gavagan,

Mayo, Sligo.

O’Gearan,

Mayo.

O’Geary,

Waterford.

O’Gevany,

Galway.

O’Gleeson,

Tipperary.

O’Glennon,

Roscommon.

O’Gloran,

Kilkenny.

O’Gogarty,

Meath.

O’Gorman,

Carlow, Clare, Fermanagh.

O’Gormley,

Donegal, Mayo.

O’Gormoge,

Mayo.

O’Grady,

Clare, Kerry, Limerick, Mayo.

O’Griffin,

Clare, Kerry.

O’Hagarty,

Kerry, Londonderry.

O’Hagerty,

Donegal.

O’Halahan,

Cork.

O’Halligan,

Meath.

O’Hallinan,

Limerick.

O’Halloran,

Clare, Galway.

O’Hamill,

Antrim, Tyrone.

O’Hand,

Meath.

O’Hanley,

Roscommon.

O’Hanlon,

Armagh.

O’Hanrahan,

Westmeath.

O’Hanratty,

Armagh.

O’Hanvey,

Down, Westmeath.

O’Hara,

Antrim, Londonderry, Mayo, Sligo.

O’Harkan,

Donegal.

O’Harney,

Kerry.

O’Hart,

Meath, Sligo.

O’Hartigan,

Cork, Limerick.

O’Haverty,

Galway,

O’Hea,

Cork, Limerick, Meath.

O’Healy,

Cork, Kerry.

O’Heaney,

Fermanagh.

O’Heffernan,

Clare, Tipperary.

O’Hehir,

Clare.

O’Heir,

Armagh.

O’Hely,

Kilkenny, Limerick.

O’Hennesey,

King’s, Westmeath.

O’Hennigan,

Cork.

O’Heoghy, or Hoey,

Down.

O’Herlihy,

Cork.

O’Heyne,

Clare, Cork, Galway.

O’Hickey,

Clare, Tipperary.

O’Higgin,

Longford, Mayo, Westmeath.

O’Hoey,

Monaghan.

O’Hogan,

Clare, Tipperary.

O’Honan,

Limerick.

O’Honeen,

Clare.

O’Hoolaghan,

Cork, King’s.

O’Hoollaghan,

Galway.

O’Horan,

Galway, Wicklow.

O’Horgan,

Cork.

O’Hosey,

Fermanagh, Tyrone.

O’Howley,

Clare, Sligo.

O’Hugh,

Donegal.

O’Hurley,

Cork, Limerick, Tipperary.

O’Hynes,

Galway.

O’Kane,

Antrim, Londonderry.

O’Kean,

Galway, Tipperary.

O’Kearney,

Clare, King’s, Tipperary, Westmeath.

O’Kearny,

Cork, Mayo.

O’Keefe,

Cork.

O’Keeley,

Clare.

O’Keely,

Kilkenny, Tipperary.

O’Keenan,

Fermanagh, Londonderry.

O’Keerin,

Mayo.

O’Keevan,

Antrim, Sligo.

O’Keiran,

Armagh.

O’Kelleher,

Cork, Kerry, Tipperary.

O’Kelly,

Down, Dublin, Galway, Kildare, Louth, Meath, Queen’s, Roscommon, Tyrone, Wicklow.

O’Kennedy,

Kerry, Tipperary.

O’Kenny,

Donegal, Roscommon.

O’Kernaghan,

Donegal, Sligo.

O’Kerrigan,

Mayo.

O’Keveny,

Kilkenny.

O’Killeen,

Mayo.

O’Kindellan,

Meath.

O’Kinealy,

Limerick.

O’Kinsellagh,

Carlow.

O’Kirwan,

Galway.

O’Kirwick,

Limerick.

O’Kissane,

Kerry.

O’Lanigan,

Tipperary.

O’Largnan,

Down.

O’Larkin,

Armagh, Galway, Wexford.

O’Larrisey,

Mayo.

O’Laverty,

Donegal, Tyrone.

O’Lavett,

Mayo.

O’Lawlor,

Down, Queen’s.

O’Lawry,

Down.

O’Leahan,

Galway.

O’Leahy,

Kerry.

O’Leaney,

Donegal.

O’Leary,

Cork.

O’Lee,

Galway.

O’Lehan or Lyons,

Cork.

O’Lenahan,

Tipperary.

O’Lennon,

Galway, Mayo.

O’Leyne,

Kerry.

O’Liddy,

Clare.

O’Loan,

Tyrone.

O’Loghlin,

Clare.

O’Loman,

Galway, Roscommon.

O’Lomasey,

Cork.

O’Lonergan,

Roscommon, Tipperary.

O’Longan,

Down.

O’Looney,

Cork.

O’Loughnan,

Down, Kilkenny, Mayo.

O’Luinin,

Fermanagh.

O’Lunney,

Tyrone.

O’Lynch,

Cavan, Clare, Cork, Down, Tipperary.

O’Lynchy,

Donegal.

O’Macken,

Down.

O’Mackesey,

Limerick.

O’Mackey,

Tipperary.

O’Madden,

Galway, King’s.

O’Maginn,

Galway.

O’Mahon,

Down.

O’Mahony,

Cork, Kerry.

O’Malbride,

Roscommon.

O’Malley,

Mayo.

O’Malone,

Westmeath.

O’Malquiney,

Tipperary.

O’Manning,

Galway.

O’MaolConry,

Roscommon.

O’Markey,

Louth.

O’Marron,

Armagh, Monaghan.

O’Meagher,

Tipperary.

O’Meaney,

Roscommon.

O’Meara,

Tipperary.

O’Meechan,

Leitrim.

O’Meehan,

Fermanagh, Sligo, Tipperary.

O’Melaghlin,

Meath, Westmeath.

O’Mellan,

Tyrone.

O’Milford,

Mayo.

O’Moghan,

Mayo.

O’Molloy,

King’s.

O’Moloney,

Clare.

O’Monahan,

Roscommon.

O’Mongan,

Sligo.

O’Mooney,

King’s, Queen’s.

O’Moore,

Down, Kerry, Queen’s.

O’Moran,

Down, Galway, Kerry, Mayo, Roscommon, Sligo.

O’Moriarty,

Kerry.

O’Morony,

Clare, Cork, Limerick.

O’Morrison,

Donegal, Sligo.

O’Morrissey,

Sligo, Tipperary.

O’Moynagh,

Sligo.

O’Mulcahy,

Limerick, Tipperary.

O’Mulclohy,

Sligo.

O’Muldoon,

Fermanagh.

O’Muldorry,

Donegal.

O’Mulfinny,

Longford.

O’Mulgee,

Donegal.

O’Mulhall,

Queen’s.

O’Mulhollan,

Londonderry.

O’Mulholland,

Antrim.

O’Mulkerrin,

Galway.

O’Mullally,

Galway.

O’Mullane,

Cork, Kerry.

O’Mullany,

Sligo, Waterford.

O’Mullarky,

Galway.

O’Mulledy,

Westmeath.

O’Mulleeny,

Mayo.

O’Mullen,

Londonderry.

O’Mulligan,

Cavan, Londonderry.

O’Mullins,

Clare.

O’Mulloy,

Roscommon.

O’Mulmoghery or Early

Donegal.

O’Mulrenin,

Mayo, Roscommon.

O’Mulrooney,

Fermanagh, Galway.

O’Mulroy,

Mayo.

O’Mulvany,

Donegal, King’s, Sligo.

O’Mulvey,

Leitrim.

O’Mulvihil,

Roscommon.

O’Muready,

King’s.

O’Murphy,

Cork, Wexford.

O’Murray,

Cavan, Donegal, Londonderry, Mayo.

O’Murrigan,

Kildare.

O’Murtagh,

Meath.

O’Naghtan or Norton.

Galway.

O’Neil, or Nihil,

Clare.

O’Neill,

Antrim, Armagh, Donegal, Down, Tyrone.

O’Neney,

Tyrone.

O’Neny,

Monaghan.

O’Neylan,

Armagh, Clare.

O’Nolan,

Carlow.

O’Noonan,

Cork.

O’Norton,

Roscommon.

O’Quigly,

Londonderry.

O’Quill,

Kerry.

O’Quinlan,

Kerry, Tipperary.

O’Quinlevan,

Clare, Tipperary.

O’Quinn,

Clare, Donegal, Limerick, Londonderry, Longford, Mayo, Tyrone.

O’Rafferty,

Donegal, Tyrone.

O’Regan,

Cork, Meath, Queen’s.

O’Reilly,

Cavan, Longford, Meath, Westmeath.

O’Riordan,

Cork.

O’Roddan,

Mayo.

O’Roddy,

Donegal.

O’Rodoghan,

Leitrim.

O’Rogan,

Down.

O’Ronan,

Longford, Mayo.

O’Ronayne,

Cork.

O’Rooney,

Down.

O’Rory,

Meath.

O’Rothlan,

Mayo.

O’Rourke,

Leitrim.

O’Ryan,

Carlow, Kilkenny, Limerick, Tipperary.

O’Scanlan,

Kerry, Limerick.

O’Scanlon,

Louth.

O’Scannell,

Cork.

O’Scullan,

Londonderry.

O’Scully,

Tipperary, Westmeath.

O’Scurry,

Galway.

O’Sexton,

Tipperary.

O’Shanahan,

Tipperary.

O’Shaughnessy,

Clare, Galway.

O’Shea,

Cork, Kerry, Kilkenny, Tipperary.

O’Sheehan,

Galway, Kerry, Limerick.

O’Sheeran,

Donegal.

O’Sheridan,

Cavan, Longford.

O’Shiel,

Antrim, Westmeath.

O’Sionagh, or Fox,

King’s.

O’Slattery,

Kerry, Tipperary.

O’Slevin,

Longford.

O’Spillan,

Tipperary.

O’Spillane,

Sligo.

O’Sullivan,

Cork, Galway, Kerry, Tipperary.

O’Talcharan,

Mayo.

O’Tarcert,

Donegal.

O’Teige or Tighe,

Wicklow.

O’Teigue,

Tyrone.

O’Tierney,

Armagh, Mayo.

O’Tolarg,

Westmeath.

O’Tomalty,

Tyrone.

O’Toole,

Galway, Kildare, Mayo, Wicklow.

O’Tormey,

Galway.

O’Tracey,

Galway.

O’Tracy,

Fermanagh.

O’Traynor,

Meath.

O’Tully,

Fermanagh.

O’Tuohy,

Cork.

O’Tuomey,

Cork.