Celtic Origin Surnames

This is a list of surnames in which the origin is Celtic. The Celtic languages are a group of related languages now spoken primarily on the British Islands and Brittany.

More Filters

usage

origin

Select filters then press SEARCH below

+Usage or language

Usage	clear
Language	clear

+Letters

Initial	clear
Start	clear
End	clear
Substring	clear
Pattern	clear help?
the letters in the pattern are compared to the letters in the name * is a wildcard that matches zero or more letters example: oo matches names which contain oo _ is a wildcard that matches exactly one letter example: __z matches names which have two letters and then z

+Meaning and keywords

Meaning	clear help?
	expand search to include grammatical forms
	expand search to include close synonyms
	expand search to include subclasses
	expand search to related names
separate search terms with spaces search for an exact phrase by surrounding it with double quotes this field understands simple boolean logic force a term to be included by preceding it with a + sign force a term to be excluded by preceding it with a - sign expand search to include grammatical forms: attempt to include grammatical forms of the meanings example: speak includes spoke expand search to include close synonyms: attempt to include synonyms of the meanings example: brave includes courageous expand search to include search narrower synonyms: attempt to include subclasses of the meanings example: reptile includes turtle expand search to related names: allow related names to inherit the meaning of the main form
Description	clear help?
	ignore name meanings
the description is the meaning and history write-up for the name separate search terms with spaces search for an exact phrase by surrounding it with double quotes example: "lord of the rings" matches names from the novel 'The Lord of the Rings' this field understands simple boolean logic force a term to be included by preceding it with a + sign force a term to be excluded by preceding it with a - sign example: +greek +(legend myth) -zeus matches Greek names of myths or legends not about Zeus ignore name meanings: keywords from the name meanings are ignored

-Origin

clear

+Source

Source

clear

+Gender

clear

+Length

clear

+Sound and syllables

Pronunciation	clear help?
	case sensitive
see the pronunciation key for a guide on how to write the sounds sounds can only be searched in names that have been assigned pronunciations * is a wildcard that will match zero or more letters in the pronunciation example: lee matches names which end with the sound lee* _ is a wildcard that will match exactly one letter in the pronunciation example: __z matches names which have two letters and then a z (s) matches exactly one syllable in the pronunciation example: (s)(s)ra matches names which have two syllables and then the sound rah (c) matches a consonant (k) matches a consonant or consonant cluster (v) matches a vowel (p) matches a plosive or stop consonant (f) matches a fricative consonant (n) matches a nasal consonant case sensitive: check this if you wish distinguish between unstressed lowercase sounds and stressed uppercase sounds
Syllables	clear help?
syllables can only be counted in names that have been assigned pronunciations names without pronunciations are excluded from results

+Relations

Related name	clear
Relationship	clear help?
	expand search to ancestral names
the "relationship" is how the name relates to its parent name example: searching for diminutive matches Betsy because it is a diminutive of its parent Elizabeth selecting *(all core forms)* excludes peripheral forms such as diminutives, short forms, and combinations expand search to ancestral names: relationships between names further up the family tree are included

+Popularity

List	clear
Year	clear
Rank	clear

+Famous namesake

Category

clear

+Options

Sort	clear
Display	clear

MacCailein Scottish Gaelic
Means "son of Cailean" in Gaelic.

MacCallion Scottish
Anglicized form of MacCailein.

MacCallum Scottish
Anglicized form of Scottish Gaelic MacColuim meaning "son of Columba".

MacCarrick Irish
Means "son of Cúcharraige" in Irish. The given name Cúcharraige is composed of cú "hound" and carraig "rock".

Mac Cárthaigh Irish
Irish Gaelic form of McCarthy.

MacCarthy Irish
Variant of McCarthy.

MacChruim Scottish Gaelic
Means "son of Crum", where Crum is a Gaelic byname meaning "bent".

Mac Cionaodha Irish
Irish Gaelic form of McKenna.

MacCionaodha Scottish Gaelic
Scottish Gaelic form of McKenna.

Mac Cléirich Irish
Means "son of the clerk" in Irish.

MacClellan Irish, Scottish
Variant of McClelland.

MacClelland Irish, Scottish
Variant of McClelland.

MacClery Irish
Anglicized form of Mac Cléirich.

Mac Cnáimhín Irish
Means "son of Cnámh". The Irish given name Cnámh means "bone".

MacCoinnich Scottish Gaelic
Scottish Gaelic form of MacKenzie.

MacColuim Scottish Gaelic
Scottish Gaelic form of MacCallum.

Mac Conmara Irish
Irish Gaelic form of McNamara.

MacConnell Scottish, Irish
Variant of McConnell.

Mac Cormaic Irish
Irish Gaelic form of McCormick.

MacCormaic Scottish Gaelic
Scottish Gaelic form of McCormick.

MacCoughlan Irish
Means "son of Cochlán". The given name Cochlán is derived from Irish cochal meaning "cape" or "hood".

MacCrum Scottish
Anglicized form of MacChruim.

MacCrumb Scottish
Anglicized form of MacChruim.

Mac Cú Uladh Irish, Scottish Gaelic
Gaelic form of McCullough.

Mac Daibhéid Irish
Irish Gaelic form of McDevitt.

MacDaniel Scottish
Variant of MacDonald.

MacDermott Irish
Variant of McDermott.

MacDhòmhnaill Scottish Gaelic
Scottish Gaelic form of MacDonald.

MacDhubhghaill Scottish Gaelic
Scottish Gaelic form of MacDougall.

MacDhubhshìth Scottish Gaelic
Scottish Gaelic form of Mac Dhuibhshíthe.

Mac Dhuibh Scottish Gaelic
Means "son of Dubh", where the byname Dubh means "dark".

Mac Dhuibhinse Irish
Irish Gaelic form of Vincent 2.

Mac Dhuibhshíthe Irish
Means "son of Duibhshíth" in Irish. The given name Duibhshíth means "black peace".

Mac Diarmada Irish
Irish Gaelic form of McDermott.

Mac Domhnaill Irish
Irish form of MacDonald.

MacDonald Scottish
Anglicized form of Scottish Gaelic MacDhòmhnaill meaning "son of Donald". It originates from the Highland clan Donald.

MacDougall Scottish
Means "son of Dougal" in Gaelic.

MacDuff Scottish
Anglicized form of Mac Dhuibh.

Mac Eachairn Scottish Gaelic
Means "son of Eacharn", where the given name Eacharn is from the Old Irish name Echthigern.

MacEachern Scottish
Anglicized form of Mac Eachairn.

MacEalair Scottish Gaelic
Scottish Gaelic form of McKellar.

MacEanruig Scottish Gaelic
Scottish Gaelic form of McKendrick.

MacEntire Scottish
Variant of MacIntyre.

Mac Eoghain Irish
Means "son of Eoghan" in Irish.

MacEòghainn Scottish Gaelic
Scottish Gaelic form of Mac Eoghain.

MacFarland Irish, Scottish
Variant of McFarlane.

MacFarlane Scottish
Variant of McFarlane.

MacFhionnlaigh Scottish Gaelic
Means "son of Fionnlagh" in Scottish Gaelic.

Mac Fhlannchaidh Irish
Irish Gaelic form of Clancy.

Mac Ghabhann Irish
Means "son of the smith" in Irish.

MacGillEain Scottish Gaelic
Scottish Gaelic form of McLean.

MacGilleChrìosd Scottish Gaelic
Scottish Gaelic form of Gilchrist.

MacGilleFhaolain Scottish Gaelic
Scottish Gaelic form of McClelland.

MacGilleMhoire Scottish Gaelic
Scottish Gaelic form of Gilmore.

MacGinnis Irish
Variant of McGuinness.

Mac Giolla Bhrighde Irish
Means "son of the servant of Brighid" in Irish.

Mac Giolla Dhuibh Irish
Irish Gaelic form of Kilduff.

Mac Giolla Eoin Irish
Irish Gaelic form of McLean.

Mac Giolla Fhaoláin Irish
Irish Gaelic form of McClelland.

Mac Giolla Mhuire Irish
Irish Gaelic form of Gilmore.

Mac Giolla Phádraig Irish
Irish Gaelic form of Kilpatrick.

Mac Giolla Rí Irish
Means "son of the king's servant" in Irish.

Mac Giolla Ruaidh Irish
Means "son of the red-haired servant" in Irish.

MacGowan Irish
Anglicized form of Mac Ghabhann.

MacGregor Scottish
Anglicized form of Gaelic MacGriogair meaning "son of Gregor". It originates from the Highland clan Gregor. A famous bearer was the Scottish folk hero Rob Roy MacGregor (1671-1734).

MacGriogair Scottish Gaelic
Scottish Gaelic form of MacGregor.

MacGrory Irish, Scottish
Variant of McCrory.

MacGuinness Irish
Variant of McGuinness.

MacGuire Irish
Variant of McGuire.

MacInnes Scottish
Anglicized form of Scottish Gaelic Mac Aonghais meaning "son of Aonghas".

MacIntosh Scottish
Variant of McIntosh.

MacIntyre Scottish
Variant of McIntyre.

Mac Íomhair Irish
Irish Gaelic form of McIver.

MacIomhair Scottish Gaelic
Scottish Gaelic form of McIver.

MacIver Scottish
Variant of McIver.

Mack 1 Scottish, Irish
Shortened form of various Irish and Scottish surnames beginning with Mac or Mc (from Irish mac meaning "son").

MacKay Scottish
Anglicized form of MacAoidh.

MacKenna Scottish
Variant of McKenna.

MacKenny Scottish
Variant of McKenna.

MacKenzie Scottish
Anglicized form of Gaelic MacCoinnich meaning "son of Coinneach". It originates from the Kintail area of Scotland on the northwest coast.

Mackintosh Scottish
Variant of McIntosh.

MacLachlainn Scottish Gaelic
Scottish Gaelic form of McLaughlin.

MacLean Scottish
Variant of McLean.

MacLeod Scottish
Variant of McLeod.

MacLeòid Scottish Gaelic
Scottish Gaelic form of McLeod.

Mac Maghnuis Irish
Irish Gaelic form of McManus.

MacMathan Irish
Variant of McMahon.

Mac Mathghamhna Irish
Irish Gaelic form of McMahon.

MacMhaoilein Scottish Gaelic
Scottish Gaelic form of McMillan.

MacMillan Scottish
Variant of McMillan.

Mac Naoimhín Irish
Means "son of Naomhán" in Irish.

MacNeachdainn Scottish Gaelic
Scottish Gaelic form of Mac Neachtain.

Mac Neachtain Irish
Means "son of Nechtan" in Irish.

MacNeil Scottish
Variant of McNeil.

Mac Néill Irish
Irish form of McNeil.

MacNèill Scottish Gaelic
Scottish Gaelic form of McNeil.

MacNevin Irish
Anglicized form of Mac Naoimhín.

Mac Niadh Irish
Means "son of Niadh" in Irish. The given name Niadh means "champion".

MacNiven Scottish
Anglicized form of Mac Naoimhín.

Mac Óda Irish
Means "son of Odo" in Irish.

Mac Pharlain Irish
Irish Gaelic form of McFarlane.

MacPhàrlain Scottish Gaelic
Scottish Gaelic form of McFarlane.

MacQueen Scottish
Anglicized form of Mac Shuibhne.

MacRae Scottish
Variant of McRae.

Mac Reachtain Irish
Ulster variant of Mac Neachtain.

Mac Ruaidhrí Irish
Irish form of McCrory.

MacRuaraidh Scottish Gaelic
Scottish Gaelic form of McCrory.

Mac Shuibhne Scottish Gaelic
Variant of Mac Suibhne.

Mac Síthigh Irish
Irish Gaelic form of McSheehy.

Mac Suibhne Irish
Means "son of Suibhne" in Irish.

MacTàmhais Scottish Gaelic
Scottish Gaelic form of McTavish.

Mac Thaidhg Irish
Irish Gaelic form of McCaig.

MacThaoig Scottish Gaelic
Scottish Gaelic form of McCaig.

Mac Uileagóid Irish
Irish Gaelic form of McElligott.

Madden Irish
Anglicized form of Ó Madaidhín.

Maddox Welsh
Derived from the given name Madoc.

Madigan Irish
Anglicized form of Ó Madaidhín.

Mag Aonghuis Irish
Irish Gaelic form of McGuinness.

Magee Irish, Scottish
Anglicized form of Mac Aodha.

Mag Eochadha Irish
Irish Gaelic form of McGough.

Magorian Irish
Possibly a variant of McGowan or McGovern.

Mag Raith Irish, Scottish Gaelic
Gaelic form of McRae.

Mag Shamhradháin Irish
Irish Gaelic form of McGovern.

Mag Uidhir Irish
Irish Gaelic form of McGuire.

Maguire Irish
Variant of McGuire.

Mahoney Irish
Anglicized form of the Irish Ó Mathghamhna meaning "descendant of Mathgamain".

Malley Irish
Anglicized form of Ó Máille.

Mallon Irish
Variant of Malone.

Malloye Irish
Variant of Molloy.

Malone Irish
Anglicized form of Irish Ó Maoil Eoin meaning "descendant of a disciple of Saint John".

Manning 2 Irish
Anglicized form of Irish Ó Mainnín meaning "descendant of Mainchín".

Markey Irish
From the Irish Ó Marcaigh meaning "descendant of Marcach", a given name meaning "horse rider".

Marvin English
Derived from the Welsh given name Merfyn or the Old English name Mærwine.

McAdams Scottish, Irish
Means "son of Adam" in Gaelic.

McAfee Scottish, Irish
Anglicized form of MacDhubhshìth.

McAlister Scottish, Irish
From Scottish Gaelic MacAlastair or Irish Gaelic Mac Alastair meaning "son of Alistair".

McArthur Scottish
Means "son of Arthur" in Gaelic.

McBride Irish
Anglicized form of Mac Giolla Bhrighde.

McCabe Irish, Scottish
Means "son of Cába", where Cába is a byname meaning "cape, cloak" (from Latin cappa).

McCaig Scottish
Anglicized form of Scottish Gaelic MacThaoig meaning "son of Tadhg".

McCallum Scottish
Variant form of MacCallum.

McCarthy Irish
Anglicized form of Irish Mac Cárthaigh meaning "son of Carthach".

McCauley Irish, Scottish
Anglicized form of Gaelic Mac Amhalghaidh or Mac Amhalghadha meaning "son of Amhalghaidh". The given name Amhalghaidh, from Old Irish Amalgaid, is of uncertain meaning.

McClain Scottish
Variant of McLain.

McCleary Irish
Anglicized form of Mac Cléirich.

McClellan Irish, Scottish
Variant of McClelland.

McClelland Irish, Scottish
From Gaelic Mac Giolla Fhaoláin meaning "son of the servant of Faolán".

McConnell Scottish, Irish
Derived from Gaelic MacDhòmhnaill (see MacDonald).

McCormick Irish, Scottish
From Gaelic Mac Cormaic meaning "son of Cormac".

McCoy Scottish
Anglicized form of MacAoidh.

McCracken Irish, Scottish
Anglicized form of Mac Reachtain, Ulster Irish variant of Mac Neachtain.

McCrae Scottish
Variant of McRae.

McCreery Irish, Scottish
Variant of McCrory.

McCrory Irish, Scottish
Anglicized form of Gaelic Mac Ruaidhrí meaning "son of Ruaidhrí".

McCrum Scottish
Anglicized form of MacChruim.

McCulloch Scottish
Scottish form of McCullough.

McCullough Irish
Anglicized form of Irish Mac Cú Uladh meaning "son of Cú Uladh". The byname Cú Uladh means "hound of Ulster". This surname has also been associated with Old Irish cullach "boar".

McCune Irish
Anglicized form of Mac Eoghain.

McDaniel Scottish
Variant of MacDonald.

McDermott Irish
Anglicized form of Irish Mac Diarmada meaning "son of Diarmaid". The McDermotts were nobility in the Kingdom of Connaught, a province in Ireland.

McDevitt Irish
Anglicized form of Irish Mac Daibhéid meaning "son of Dáibhí".

McDonald Scottish
Variant of MacDonald.

McDougall Scottish
Variant of MacDougall.

McDowell Scottish
Variant of MacDougall.

McEachern Scottish
Anglicized form of Mac Eachairn.

McElligott Irish
Anglicized form of the Irish Gaelic name Mac Uileagóid meaning "son of Uileagóid", a diminutive of Uilleag.

McEwan Scottish
Anglicized form of MacEòghainn.

McFarland Irish, Scottish
Variant of McFarlane.

McFarlane Scottish, Irish
Anglicized form of Scottish Gaelic MacPhàrlain or Irish Gaelic Mac Pharlain meaning "son of Parthalán".

McFee Scottish, Irish
Anglicized form of MacDhubhshìth.

McGee Irish, Scottish
Anglicized form of Mac Aodha.

McGill Irish, Scottish
Anglicized form of Gaelic Mac an Ghoill meaning "son of the foreigner", derived from gall "foreigner".

McGinnis Irish
Variant of McGuinness.

McGough Irish
Variant of Gough 2.

McGovern Irish
Anglicized form of Irish Gaelic Mag Shamhradháin meaning "son of Samhradháin", a given name meaning "summer".

McGowan Irish
Anglicized form of Mac Ghabhann.

McGregor Scottish
Variant of MacGregor.

McGuinness Irish
Anglicized form of Irish Mag Aonghuis meaning "son of Aonghus".

McGuire Irish
Anglicized form of Irish Mag Uidhir meaning "son of Odhar", a given name meaning "pale-coloured".

McInnes Scottish
Variant of MacInnes.

McIntosh Scottish
From Scottish Gaelic Mac an Tòisich meaning "son of the chief".

McIntyre Scottish
From Scottish Gaelic Mac an tSaoir meaning "son of the carpenter".

McIver Scottish, Irish
Anglicized form of Gaelic MacIomhair meaning "son of Íomhar".

McKay Scottish
Anglicized form of MacAoidh.

McKee Scottish, Irish
Anglicized form of Mac Aodha.

McKeever Irish
Variant of McIver.

McKellar Scottish
From Gaelic MacEalair meaning "son of Ealar".

McKendrick Scottish
Anglicized form of Gaelic MacEanruig meaning "son of Eanraig".

McKenna Irish, Scottish
Anglicized form of Gaelic Mac Cionaodha meaning "son of Cionaodh".

McKenzie Scottish
Variant of MacKenzie.

McKinley Scottish
Anglicized form of MacFhionnlaigh. This name was borne by the American president William McKinley (1843-1901), who was assassinated.

McKinney Irish, Scottish
Variant of McKenna.

McKowen Irish
Anglicized form of Mac Eoghain.

McLachlan Scottish
Variant of McLaughlin.

McLain Scottish
Variant of McLean.

McLaughlan Scottish
Variant of McLaughlin.

McLaughlin Scottish
Anglicized form of Gaelic MacLachlainn meaning "son of Lachlann".

McLean Scottish
Anglicized form of Gaelic MacGillEathain or MacGillEain meaning "son of the servant of Eòin".

McLeod Scottish
From Gaelic MacLeòid meaning "son of Leod", a given name derived from Old Norse ljótr "ugly".

McMahon Irish
Anglicized form of Irish Mac Mathghamhna meaning "son of Mathgamain".

McManus Irish
Anglicized form of Irish Mac Maghnuis meaning "son of Mághnus".

McMillan Scottish
Anglicized form of Gaelic MacMhaoilein meaning "son of Maolan", itself meaning "devotee, servant, tonsured one".

McNab Scottish, Irish
Anglicized form of Gaelic Mac an Aba meaning "son of the abbot".

McNabb Irish, Scottish
Variant of McNab.

McNamara Irish
From Irish Mac Conmara meaning "son of Conmara". The given name Conmara is composed of cú "hound" and muir "sea".

McNaughton Irish, Scottish
Anglicized form of Mac Neachtain.

McNeal Scottish
Variant of McNeil.

McNee Irish
Anglicized form of Mac Niadh.

McNeil Scottish
Anglicized form of Gaelic MacNèill meaning "son of Niall".

McNeill Scottish, Irish
Variant of McNeil.

McNeilly Scottish
Anglicized form of Gaelic Mac an Fhilidh meaning "son of the poet".

McNiel Scottish
Variant of McNeil.

McNiven Irish
Anglicized form of Mac Cnáimhín.

McPhee Scottish
Anglicized form of MacDhubhshìth.

McQueen Scottish
Anglicized form of Mac Shuibhne.

McRae Scottish
From Gaelic Mag Raith meaning "son of Rath", a given name meaning "prosperity" or "grace".

McReynolds Scottish, Irish
Means "son of Reynold" in Gaelic.

McSheehy Irish
Anglicized form of Irish Gaelic Mac Síthigh, meaning "son of Sítheach".

McTaggart Scottish
Variant of Taggart.

McTavish Scottish
Anglicized form of Gaelic MacTàmhais meaning "son of Tàmhas".

Meaney Irish
Variant of O'Mooney.

Merrick Welsh
Derived from the given name Meurig.

Merricks Welsh
Variant of Merrick.

Merrill 1 English
Derived from the given name Muriel.

Meyrick Welsh
Variant of Merrick.

Milligan Irish
Anglicized form of the Irish Ó Maolagáin meaning "descendant of Maolagán", a given name derived from maol meaning "bald" or "tonsured".

Mohan Irish
Anglicized form of Irish Ó Mocháin meaning "descendant of Mochán".

Mollown Irish
Variant of Malone.

Molloy Irish
Anglicized form of Ó Maolmhuaidh or Ó Maol Aodha.

Moloney Irish
From Irish Ó Maol Dhomhnaigh meaning "descendant of a church servant".

Monaghan Irish
Variant of Monahan.

Monahan Irish
From Irish Ó Manacháin meaning "descendant of Manacháin". The given name Manacháin meant "little monk", from manach "monk" and a diminutive suffix.

Monday 3 Irish
Anglicized form of Mac Giolla Eoin. The last part of the surname was mistakenly taken as the Gaelic word for "Monday", Luain.

Monroe Scottish
Anglicized (typically American) form of Munro. It was borne by the American actress Marilyn Monroe (1926-1962).

Moon 3 Irish
Variant of Mohan.

Mooney Irish
Variant of O'Mooney.

Moran Irish
Anglicized form of Irish Ó Móráin meaning "descendant of Mórán", a given name meaning "great, large".

Morgan Welsh
Derived from the given name Morgan 1.

Moriarty Irish
From Irish Ó Muircheartach meaning "descendant of Muirchertach". This was the surname given by Arthur Conan Doyle to a master criminal in the Sherlock Holmes series.

Morris English, Irish, Scottish, Welsh
Derived from the given name Maurice.

Mullane Irish
Variant of Mullen.

Mullen Irish
From the Irish Ó Maoláin meaning "descendant of Maolán". The given name Maolán meant "devotee, servant, tonsured one".

Mulligan Irish
Variant of Milligan.

Mullins 2 Irish
Variant of Mullen.

Mulloy Irish
Variant of Molloy.

Mulrennan Irish
Anglicized form of Ó Maol Bhréanáin.

Mulryan Irish
Anglicized form of Ó Maoil Riain.

Munro Scottish
Designated a person who had originally lived near the mouth of the Roe River in Derry, Ireland. It is derived from Gaelic bun meaning "root, base" combined with the river's name.

Munroe Scottish
Anglicized (typically Canadian and American) form of Munro.

Murdoch Scottish
Scottish form of Murdock.

Murdock Irish
Derived from the given name Murchadh.

Murphy Irish
Anglicized form of Irish Ó Murchadha meaning "descendant of Murchadh". This is the most common Irish surname.

Murray 2 Irish
Anglicized form of Irish Ó Muireadhaigh meaning "descendant of Muireadhach".

Neal English
Derived from the given name Neil.

Neely Scottish
Variant of McNeilly.

Neil Scottish, English, Irish
Derived from the given name Neil.

Nelson 1 English
Means "son of Neil". This name was borne by the British admiral Horatio Nelson (1758-1805).

Neville English, Irish
From the names of towns in Normandy, variously Neuville or Néville, meaning "new town" in French.

Nevin 1 Irish
Anglicized form of Mac Naoimhín.

Nevin 2 Irish
Anglicized form of Mac Cnáimhín or Ó Cnáimhín.

Nielson English
Variant of Nelson 1.

Nigel English
Derived from the given name Neil.

Niles English
Means "son of Neil".

Niven Scottish
Anglicized form of Mac Naoimhín.

Nolan Irish
Anglicized form of Irish Ó Nualláin meaning "descendant of Nuallán".

Ó Baoghill Irish
Irish Gaelic form of Boyle.

O'Beirne Irish
Variant of O'Byrne.

O'Berne Irish
Variant of O'Byrne.

O'Boyle Irish
Variant of Boyle.

Ó Brádaigh Irish
Irish Gaelic form of Brady.

Ó Bradáin Irish
Irish Gaelic form of Braden.

Ó Braoin Irish
Irish Gaelic form of Breen.

Ó Braonáin Irish
Irish Gaelic form of Brennan.

Ó Briain Irish
Irish Gaelic form of O'Brien.

O'Brian Irish
Variant of O'Brien.

O'Brien Irish
From the Irish Ó Briain meaning "descendant of Brian".

Ó Broin Irish
Irish Gaelic form of O'Byrne.

Ó Buachalla Irish
Irish Gaelic form of Buckley 2.

O'Byrne Irish
Anglicized form of Irish Ó Broin meaning "descendant of Bran 1".

Ó Caiside Irish
Irish Gaelic form of Cassidy.

O'Callaghan Irish
Variant of Callahan.

Ó Caoimh Irish
Irish Gaelic form of Keefe.

Ó Caoimháin Irish
Irish Gaelic form of Cavan.

Ó Caoindealbháin Irish
Irish Gaelic form of Quinlan.

Ó Caolaidhe Irish
Irish Gaelic form of Keeley.

Ó Carra Irish
Means "descendant of Carra", Carra being a nickname meaning "spear".

Ó Catháin Irish
Means "descendant of Cathán".

Ó Cathaláin Irish
Irish Gaelic form of Callan.

Ó Cathasaigh Irish
Irish Gaelic form of Casey.

Ó Ceallacháin Irish
Irish Gaelic form of Callahan.

Ó Ceallaigh Irish
Irish Gaelic form of Kelly 1.

Ó Cearmada Irish
Irish Gaelic form of Carmody.

Ó Ceithearnaigh Irish
Irish Gaelic form of Kearney.

Ó Ciardha Irish
Irish Gaelic form of Carey.

Ó Cinnéidigh Irish
Irish Gaelic form of Kennedy.

Ó Cléirigh Irish
Means "descendant of the clerk" in Irish.

O'Clery Irish
Anglicized form of Ó Cléirigh.

Ó Cnáimhín Irish
Means "descendant of Cnámh", Cnámh being a nickname meaning "bone".

Ó Cochláin Irish
Means "descendant of Cochlán", where the given name Cochlán is derived from Irish cochal "cape" or "hood". This surname originated in County Cork, Ireland.

Ó Coigligh Irish
Irish Gaelic form of Quigley.