Irish Family Names C
O'CAHAN, O'KANE, KEANE
NAME ON MAP: O'CATHAIN MODERN COUNTY: Londonderry MEANING: the name is recorded in the Annals from 1170 and meant `descendant of Cathán'. (The name derived from cath `battle' and the diminutive suffix án `little'.)
O'CALLAGHAN, KELAGHAN
NAME ON MAP: O'CEALLACHAIN MODERN COUNTY: Cork MEANING: `descendant of Ceallachán'. He was King of Munster and died in 952. (The name came from ceallach `strife'.) The sept had been driven into County Cork by Anglo-Norman pressure by 1300.
O'CALLAN
NAME ON MAP: O'CATHALAIN MODERN COUNTY: Monaghan MEANING: `descendant of Cathalann'. (The name derived from cathgal `battle, mighty' and the diminutive suffix án.)
MacCANN
NAME ON MAP: MacCANA MODERN COUNTY: Armagh MEANING: `son of Cana'. (The name meant `wolf cub'.) Amhlaigh MacCanna, died 1155, was described in The Four Masters as a `pillar of chivalry and vigour'. The sept was last mentioned in the Annals in 1250 and was in decline at the date of this map.
CARDWELL, MacARDLE
NAME ON MAP: MacÁRDGAIL MODERN COUNTY: Louth MEANING: `son of Ardgal'. (The name derived from árd `height' and gal `valour'.) The sept was a branch of the MacMahons.
O'CARROLL
NAME ON MAP: O'CEARBHAIL MODERN COUNTY: Offaly MEANING: `descendant of Cearbhall'. (The name came from cearbh `hacking', hence `fierce warrior'.) Only one out of six early septs of this name, that in Offaly, know as the Ely O'Carrolls, survived the Anglo-Norman invasion intact, although individual O'Carrolls remained in many places.
MacCARTHY
NAME ON MAP: MacCARTHAIGH MODERN COUNTY: Cork MEANING: `descendant of Cárthach', specifically Cárthach, the Lord of Eoghannacht, who was burnt by his enemies in his house in 1045. The Eoghannacht themselves claimed descent from the legendary Eoghan, one of the two sons of Oiloll Olum, reputed King of Munster the 3rd century. (Cárthach meant `loving'.) There were three septs in Kerry: MacCarthys Mór (great), Muskerry (descended from the legendary Carbery Musc, son of King Conary II of Ulster) and Reagh (riabhach `grey').
O'CASEY
NAME ON MAP: O'CATHASAIGH MODERN COUNTY: Dublin MEANING: `descendant of Cathasach'. (The name meant `watchful'.) It was a common name with six unrelated septs before 1200; in 1300 the most important was in County Dublin.
O'CASSIDY
NAME ON MAP: O'CAISIDE MODERN IRISH NAME: O'Caiside MODERN COUNTY: Fermanagh MEANING: `descendant of Caiside'. (The name was a nick-name related to cas meaning `curly-headed'.) The O'Cassidys were the hereditary physicians to the Maguires from 1300-1600. The renowned poet Giolla Moduda O'Caiside died in 1143.
CLEAR, CLARE
NAME ON MAP: CLERE (from a 1290 record) MODERN IRISH NAME: de Cléir MODERN COUNTY: Waterford MEANING: the name came from the village of Clare in Suffolk, England and ultimately from a BRITISH river name possibly meaning `bright' or `gentle'. Nicholas de Clere was a descendant of Richard Fitzgilbert de Clare, Earl of Pembroke, nicknamed Strongbow, who led the Anglo-Norman invasion in 1170 and died in 1176.
O'CLERY, CLERK
NAME ON MAP: O'CLEIRIGH MODERN COUNTY: Donegal MEANING: `descendant of Cleirach'. (The name derived from cléireach `clerk, cleric'.) Cleirach, who was born about 820, was descended from King Guaire the Hospitable of Munster. The sept was one of the first to use a surname. It was dispersed from Co. Galway by about 1250 and settled in Donegal and Derry (where it produced notable poets) and to a lesser extent in Cavan and Kilkenny.
O'COLLINS
NAME ON MAP: O'COILEAIN MODERN COUNTY: Cork MEANING: `descendant of Coileán'. (The name derived from coileán `puppy, whelp'.) Originally from Limerick, the sept was pushed south into Cork by the Fitzgeralds during the 12th century, settling in an area held by a small unrelated sept called ? Cuilleáin, a name which coincidentally is also anglicized as Collins.
O'CONNELL
NAME ON MAP: O'CONAILL MODERN COUNTY: Kerry MEANING: `descendant of Connall'. (The name possibly derived from con, itself derived from cú `hound', and gal `valour'.) The family traditionally descended from the legendary Aengus Tuirmeach, High King of Ireland in about 280 BC. There was a Bishop O'Conaill of Thomond in 927, who may have been one of the first Irishmen to have had a surname.
O'CONNOLLY
NAME ON MAP: O'CONGHALAIGH MODERN IRISH NAME: O'Conghaile MODERN COUNTY: Monaghan MEANING: `descendant of Conghalach'. (The name meant `valiant'.) The sept in modern Monaghan was one of the legendary Tribes of Tara in County Dublin before being driven north by the Anglo-Norman invaders. The O'Connollys in Munster (not shown on the map) derive from a separate sept, called O'Coingheallaigh.
O'CONNOR, O'CONOR
NAME ON MAP: O'CONCHOBHAIR MODERN COUNTIES: Sligo, Roscommon, Kerry MEANING: The O'Connors Don (brown), Rua (red) and Sligo were all descendants of King Conchobhar of Connacht, who died in 971. The O'Connor Kerry sept came from a different Conchobhar. (The name derived from con, itself derived from cú `hound', and cobhar `desiring'.) Toirrdelbach O' Conchobhair (Turlough O'Connor), King of Connacht, 1106-56, was the greatest warrior of his age and became high-king of Ireland. Ruaidhri O'Conchobhair (Rory O'Connor) was high-king at the time of Strongbow's invasion and retired to the abbey of Cong in 1183. (See the entry for MacMurrough).
O'CORRY, CORR, SOME CURRYS
NAME ON MAP: O'CORRA MODERN COUNTY: Tyrone MEANING: `descendant of Corra'. (The name derived from cor `spear, pointed object'.) The most important sept was in south west Tyrone, although many Ulster O'Corrys descend from a Gilla Corra in eastern Tyrone who appears in the Annals of Ulster in 1186. The modern surname Curry may also derive from ? Comrhraidhe and in many cases from later Scottish immigrants from Dumfries.
O'COSGRAVE, COSGROVE
NAME ON MAP: O'COSCRAIGH MODERN COUNTY: Wicklow MEANING: `descendant of Coscrach'. (The name, meaning `victorious, triumphant', derived from coscu `victory'.) There were two unrelated less important septs in Galway and Ulster (not shown).
MacCOSTELLO
NAME ON MAP: MacOISDEALBH (from an 1193 record) MODERN IRISH NAME: MacOisdealbhaigh MODERN COUNTY: Mayo MEANING: `son of Oisdealbhach'; (the name derived from os `fawn' and dealbhadh `in the form of'). He was the son of an Anglo-Norman, Gilbert de Nangle, from Angle in Pembrokeshire, Wales. Nangle was a corruption of OLD ENGLISH atten angle, a descriptive phrase related to NORSE ongul `fishing hook', meaning `at a bend'. It was the first Anglo-Norman family to adopt a `Mac' name.
MacCOYLE, MacCOOL
NAME ON MAP: Mac GIOLLA CHOMHGAILL MODERN IRISH NAME: Mac Giolla Chomhgail MODERN COUNTY: Donegal MEANING: `son of a follower of St Comhgal'. There were two separate septs in Donegal, the MacCools holding land to the south of the MacCoyles.
CRUISE
NAME ON MAP: De CRUYS (from a 13th century record) MODERN IRISH NAME: de Crúis MODERN COUNTY: Dublin MEANING: this was an Anglo-Norman name derived from MIDDLE ENGLISH crus `bold, fierce'.
O'CULLEN
NAME ON MAP: O'CUILINN MODERN COUNTIES: Kildare, Wicklow MEANING: `descendant of Cuileann'. (The name meant `holly'.) A powerful early sept on the eastern borders of County Kildare, its power had been largely eclipsed by the O'Tooles and the O'Byrnes by about 1300.