Irish surnames starting with L

The L names in brief

• Lacey · de Léis · Norman & Gaelic sept
  Norman ‘de Laci’, of Lassy in France; or Ó Laitheasa, descendant of Flaitheas. There are two unrelated names here. The Norman de Lacys came to England with William the Conqueror, and at the Anglo-Norman invasion Hugh de Lacy was granted the whole of Meath.
• Lalor · Ó Leathlobhair · Gaelic sept
  Descendant of Leathlobhar. Leathlobhar means half-leper. An Ulster family descended from Leathlobhar, King of Ulidia, who died in 871, disappear from the record after the 10th century.
• Langan · Ó Longáin · Gaelic septs (several)
  Descendant of Longán, a diminutive of long, ‘tall’. Woulfe names two families. One was an Ulster family, anciently chiefs of West Uí Breasail in Co.
• Larkin · Ó Lorcáin · Gaelic sept
  Descendant of Lorcán, 'fierce'. Lorcán is from lorc, fierce, and Woulfe lists several families: a royal Leinster family in the barony of Forth in Wexford; an Oriel family, lords of Uí Nialláin and of Farney, still numerous in Armagh; a Galway family of the O'Maddens' stock; a Meath family; and erenaghs of Lorrha in Tipperary. Jim Larkin led the Dublin workers in the Lockout of 1913.
• Laverty · Ó Laithbheartaigh · Gaelic sept
  Descendant of Flaithbheartach. The same name as Ó Flaithbheartaigh, with the f softened away. Woulfe calls it a distinguished family of the Cinéal Eoghain in Ulster, still common especially in Tyrone, Derry, Antrim and Donegal.
• Lavin · Ó Láimhín · Gaelic sept
  A corruption of Ó Flaithimhín. Followers of MacDermot Roe in Roscommon, Woulfe writes, and still common there and in Mayo. Supposed to come from lámh, a hand, the name was sometimes put into English as Hand; Woulfe believed it really a corruption of Ó Flaithimhín.
• Lawless · Laighléis · Norman-English
  Middle English ‘Laghles’, the outlaw. The family came into Ireland around the time of the Anglo-Norman invasion, Woulfe writes, and spread through Leinster and Munster. A branch also settled in Tirawley, Co.
• Leahy · Ó Laochdha · Gaelic sept
  Descendant of Laochdha, 'heroic'. An old Munster surname, Woulfe writes, very common in Cork, Kerry, Limerick and Tipperary. He warns against confusing it with Ó Lathaigh, which is sometimes also anglicised Leahy.
• Lehane · Ó Liatháin · Gaelic sept
  Descendant of Liathán, 'grey'. Woulfe finds two families: one in Cork, which O'Donovan took to be one of the families formed when the old clan of Uí Liatháin divided, and one of the Uí Fiachrach at Dromard in Sligo. The Sligo family seems to have moved to Donegal.
• Lenihan · Ó Léanacháin · Gaelic sept
  Descendant of Léanachán, 'mantled, cloaked'. Woulfe makes Ó Léanacháin a Roscommon family, still numerous but dispersed through Connacht. Lenihan is also one of the English forms of a different name, Ó Luingeacháin (see Linehan).
• Lennon · Ó Leannáin · Gaelic sept
  Descendant of Leannán, 'lover' or 'sweetheart'. Several unrelated septs share the name, including a Fermanagh family who were keepers of relics for the Maguires. Also recorded as Ó Lionáin, from lonán, 'blackbird'.
• Linehan · Ó Luingeacháin · Gaelic sept
  Descendant of Longachán. Woulfe calls Ó Luingeacháin a softened form of Ó Longacháin, apparently replacing the old east Limerick or Tipperary surname Mac Longacháin, and common in Cork, Limerick and Kerry. Linehan and Lenihan are both among its forms, so a Munster Lenihan is more likely of this family than of the Roscommon Ó Léanacháin.
• Loftus · Ó Lachtnáin · Gaelic sept (renamed)
  Descendant of Lachtnán, 'milk-white'. In Mayo, Loftus is often a disguise for Ó Lachtnáin, from Lachtna, grey: chiefs of the Two Bacs and Glen Nephin in Tirawley, who gave bishops to Connacht sees in the 13th and 14th centuries. Woulfe lists other families of Ó Lachtnáin in Teffia, Oriel, Uí Maine and elsewhere, and notes that the name was often corrupted to Loughlin or Loughran.
• Lombard · Lombard · Italian-Norman
  'the Lombard' — an Italian banker. Le Lombard, a native of Lombardy, and later a banker or money-lender. There were old merchant families of the name in Cork, Waterford and Buttevant.
• Lonergan · Ó Longargáin · Gaelic sept
  Descendant of Longargán, a diminutive of lonngarg, ‘strong-fierce’. A Dalcassian family seated in the east of Thomond until after 1318, when the O'Briens and MacNamaras drove them out and they settled in Co. Tipperary.
• Looney · Ó Luanaigh · Gaelic sept
  Descendant of Luanach, 'warrior' (luan, champion). Ó Luanaigh, from luan, a warrior or champion. Woulfe describes it as a Munster surname found chiefly in Cork and Clare, with Lowney among its forms.
• Loughran · Ó Luchaireáin · Gaelic sept
  Descendant of Luchaireán, 'bright, glittering'. A celebrated ecclesiastical family of east Ulster, Woulfe writes, especially in the diocese of Armagh. Elsewhere Loughran can also come from Ó Lachtnáin.
• Lowry · Ó Labhradha · Gaelic sept
  Descendant of Labhraidh, ‘speaker, spokesman’. An ancient family in Co. Down, Woulfe writes, where the name was still common.
• Lucey · Ó Luasaigh · Gaelic sept
  A corruption of Mac Cluasaigh. A well-known Co. Cork surname.
• Lunney · Ó Luinigh · Gaelic sept
  Descendant of Luineach. A family of Cinel Moen in Ulster, Woulfe writes, first in the barony of Raphoe until the O'Donnells drove them across the Foyle into Tyrone, where they named the district Muinter Loony. By 1923 the name was very common in Fermanagh.
• Lydon · Ó Lodáin · Gaelic sept
  Descendant of Lodán. Woulfe calls Ó Lodáin a common surname in many parts of Connacht and in Clare, with older forms probably Ó Lotáin. He gives no meaning for the ancestor's name.
• Lynam · Ó Laidhghneáin · Gaelic sept
  Descendant of Laidhghneán, 'snow-birth'. An ecclesiastical family of Leinster, Woulfe writes, erenaghs of Ferns and of St Mullins in Carlow; many churchmen of the name in the Annals probably belonged to it. Still common in Leinster, and by his time generally anglicised Lynam.
• Lynch · Ó Loingsigh / de Lench · Gaelic sept & Norman tribe
  Descendant of Loingseach, 'mariner'. Loingseach means having a fleet, a mariner, and Woulfe lists at least seven separate Ó Loingsigh families: chiefs of Dál Riada in Antrim and Down in the 11th century, dispossessed by the Normans but still numerous there; chiefs of Owney in Tipperary until the O'Mulryans took it; a strong clan in Bréifne, chiefs of Cinéal Bacaid, still numerous in Cavan; a Dál gCais family in Clare and Limerick; a branch of the Corca Laoighdhe in west Cork; a Uí Fiachrach family in Sligo; and one in Meath. The Lynches of Galway, one of the city's merchant Tribes, were a separate family of Norman origin.
• Lyons · Ó Laighin · Gaelic sept
  Descendant of Laighean, 'lance, spear'. Woulfe finds three families of Ó Laighin: in Galway, holding property in the barony of Kilconnell to the end of the 17th century; in Kildare, at Kill near Naas; and an old Kerry family. The name had become very common all over Ireland as Lyons, Lyne and Lane.
• Lysaght · Mac Giolla Iasachta · Gaelic sept
  Son of Giolla Iasachta, ‘strange youth’. A well-known Clare surname. Woulfe says the family is said to be a branch of the O'Briens, descended from Domhnall Mór Ó Briain, King of Munster (1163–1194).

Also spelled with L

These are listed on the atlas under another spelling, but the L form is the one many families carry.