Doag or Doak. Used for Davock in the Ulster Province.

Dobbin / Doibin / Dod / Robert. English origins. They were in Co. Kilkenny in the south - west of Southern Leinster and nearby in Co. Waterford in the south - east of the Munster Province in 14th Century AD.

Dobbin / Doibin. English origins. They were in Co. Antrim in the north - east of the Ulster Province.

Dobbs / Robert. English origins. They were in Co. Antrim in the north - east of the Ulster Province in the 16th Century AD and were at Castledobbs.

Dobson. English origins. They were in Co. Leitrim in Northern Connacht.

Mac Dockery - Irish / Mheic Dhail Re Dochair. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Briuin Ai Siol Muiredaigh Clann Dail  Sept / Family branch, who were kinsmen to the Ui Briuin O Connor Kings of Connacht and Ireland. They had their territory in Co. Roscommon in the east of the Connacht Province. Their Irish name was eventually corrupted to Mheic Giolla Deachair and then because of this anglicized also as Harden and Hardy - deacair / hard. Ua Dochraigh now also used, which is incorrect. Kinsmen also to the Mac Dermots, Mac Donaghs etc. Ancestors - *87.Brion the original 1st King of Connacht (Ui Briuin), *86.Eochy "Mugmedon" the 124th King of Tara / Ireland..

O Docherty or O Dogherty - Irish / Ua Dochartaig - dochartach / stern. A Sept / Family branch, who had their territory in Co. Donegal in the north - west of the Ulster Province and throughout Ulster.

O Docherty or O Dogherty - Irish / Ua Dubhhatagh. A Sept / Family branch, who had their territory in Co. Tipperary in the north - east of Ormond / Aur Mhumhain / North Eastern Munster.

Dodd. English origins. They came from Shropshire to Co. Sligo in the north - west of the Connacht Province in the late 16th Century AD and are now mostly in Co. Antrim and Co. Down in the east of the Ulster Province. Also used there as a synonym for Dowd, which see.

Doey or Dooey. Used as variants for Duffy, which see, in the north - east of the Ulster Province.

Dogget. English origins. They have been in the Leinster Province since the 13th Century AD.

O Doheny or O Downey - Irish / Ua Dubhchonna. An Ithian Corca Laoidhe Sept / Family branch, who had their territory in Co. Cork in Desmond / Des Mhumhain / Southern Munster and some migrated to Ormond in the north east of Munster where it was changed to O Dawney. Ancestors - *36.Lewy / Lughaidh, *35.Ith (Ithians).

O Doherty - Irish / Ua Dochartaigh - dochartach / hurtful. A Heremonian Ui Cobhthaigh Dal Cuinn "Northern" Ui Niaill Cenel Conaill Sept / Family branch, whose territory was at Inishowen in Co. Donegal in the north - west of the Ulster Province. Also see O Doorty and O Dorrity. Ancestors - *88.Conall "Gulban" the 1st King of Tir Conaill / Tyrconnell (Cenel Conaill), *87.Niall of the Nine Hostages the 126th King of Tara / Ireland (Ui Niaill).

O Dolain - Irish / Ua Dubhshlain - dubh / black / slan - challenge / defiance. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Maine Sept / Family branch, who had their territory in the south of Co. Roscommon and the east of Co. Galway in Southern Connacht. Ancestors - *86.Maine "Mor"(Ui Maine), *85.Murray / Muiredach "Tireach" the 122nd King of Tara / Ireland, *80.Conn of the Hundred Battles the 110th King of Tara / Ireland (Dal Cuinn).

O Dolain - Irish / Ua Doibhilin - dobhail / unlucky. Anglicized as O Devlin, which see, in Co. Sligo in the north - west of the Connacht Province. They were also in Co. Cavan in Southern Ulster, and Co. Mayo in the mid - west of Connacht.

O Dolan. Originally O Doelan - Irish / Ua Doibhailen. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Maine Sept / Family branch, who had their territory at Clonmacnowen in Co. Galway in Southern Connacht and nearby to Athlone in Co. Roscommon in the east of Connacht. Now also in Co. Leitrim in Northern Connacht, Co. Cavan in Southern Ulster and Co. Fermanagh in the south - west of Ulster. Ancestors - *86.Maine "Mor"(Ui Maine), *85.Murray / Muiredach "Tireach" the 122nd King of Tara / Ireland, *80. Conn of the Hundred Battles the 110th King of Tara / Ireland (Dal Cuinn).

O Dolan - Irish / Ua Dubhhlain / Ua Dobhailen. An Irian Laeghis / Ui Laoighis Sept / Family branch, of the O More / Moore / Ui Morda Sept, whose original territory was in Co. Laois in the mid - west of Southern Leinster. Anglicized also as O Doolan, and Especially see - O Dowling,

Dolier / de Olier. French Huguenot origins. They were in Co. Dublin in the north - east of Southern Leinster.

Dollard or Dullard. They were in Co. Dublin in the north - east of Southern Leinster since the 13th Century AD.

O Dolly - Irish / Ua Dathlaoich - laoch / hero or champion / dath / swift. An important Sept / Family branch, who had their territory in the Connemara in Co. Galway in Southern Connacht.

O Dolohunty. Used as a variant for O Delahunty, which see.

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