O Lavelle. Originally Mulfaal - Irish / Ua Maolfhabhail - faball / movement. A Sept / Family branch, who had their  territory in Co. Mayo in the mid - west of the Connacht Province and were also in Co. Donegal in the north - west of the Ulster Province. Also corrupted to Fall and Melville, which see.  

O Laverty or O Lafferty or O Laherty - Irish / Ua Flaithbertaig. A Heremonian Ui Cobhthaigh Dal Cuinn "Northern" Ui Niaill Cenel nEogain Clann Domnaill na Dalaigh Sept / Family branch, who had their territory in Co. Donegal and nearby in Co. Tyrone in the Ulster Province where they were the Chiefs of Aileach and the Tanaiste / Princes of Co. Tyrone in Central Ulster. Etymologically the same as O Flaverty.  Ancestors - *100.Donnell, *99.Aed "Findliath," *98.Niall "Caille," *97.Aed "Oirdnide," *96.Niall "Frossach," *95.Fergal the 151st King of Tara / Ireland,*94.Mael "Duin," *93.Mael "Fithrich," *92. Aed "Uardidnach, *91.Donnell / Domhnall "Ilchegach," *90.Murtough / Muirchertach mac Ercae, *89.Murray / Muiredach the 2nd King of Aileach, *88.Eogan the 1st King of Aileach (Cenel nEogain), *86.Niall of the Nine Hostages the 126th King of Tara / Ireland (Ui Niaill).

Mac Laverty - Irish / Mheic Fhlaithbheartaigh. A Sept / Family branch, who had their territory in the Ulster Province. May be akin to O Laverty, which see.

O Lavery or O Lowry - Irish / Ua Labradha - labraidh / spokesman. They had 3 Septs / Family branches, Lavery "Baun" - ban / white. Lavery "Roe"- rua / red, Lavery "Trin" - trean / strong. Some of those from the "Trin" Sept changed their name to Armstrong. Their territory was in Co. Antrim and nearby in Co. Down in the east of the Ulster Province.

Mac Lavery. A Heremonian Ui Cobhthaigh Dal Cuinn Colla da Crioch Airthir Ui Echdach Ui Echach Orior Siol Ciarain Ui nEchach Clann Ruadhagain Sept / Family branch, who had their territory in the north of Co. Armagh in the south - east of the Ulster Province and nearby in Co. Down. Especially see - Mac Glory.

Lavey. May be a variation of Leavy, which see, who were in Co. Longford in the north - west of Northern Leinster and it was also used nearby in Co. Westmeath in the south - west of Northern Leinster.

O Lavin - Irish / Ua Laimhain - lamhain. May have been originally flaithimhin / ruler. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Briuin Sept / Family branch, who had their territory in Co. Roscommon in the east of the Connacht Province under the Heremonian Ui Cobhthaigh Dal Cuinn Ui Briuin Mac Dermots. Some changed to Hand by mistranslation. Ancestors - *87.Brion the original 1st King of Connacht (Ui Briuin), *86.Eochy "Mugmedon" the 124th King of Tara / Ireland.

O Lavin. A Heremonian Ui Cobhthaigh Dal Cuinn Colla da Crioch Siol Daim Argait Sept / Family branch. Ancestors - *101.Dalach, *100.Odhar / Uidhir, *85.Murray / Muiredach "Colla da Crioch" / "Focrith" - of the Two Countries, *84.Eochy / Echu "Doimhlen," *83.Cairbre "Liffeachair" the 116th King of Tara / Ireland.

Mac Lavin. See - Mullavin.

Law or Lawe. English origins. They were in the north - east of the Ulster Province.

Lawder or Lauder - laidir / strong. They were in the Leinster Province.

Lawell. Used as a synonym for Lavelle, which see.

Lawlee. English origins. Used as a synonym for Lawley, which see. They were initially in Co. Westmeath in the south - west of Northern Leinster and also in the Ulster Province and Co. Cork in Southern Munster.

Lawless or Lawles / Laighleis / laghles / outlaw. English origins. They came into Ireland after the Anglo - Norman Invasion and were initially one of the "10 Foreign Tribes of Kilkenny" in Co. Kilkenny / Ossory in the south - west of Southern Leinster with territory also in Co. Dublin in the north - east of Southern Leinster with one becoming a Burgess of Kilkenny City in 1396 AD. They are now to be found in Co. Galway and nearby in Co. Mayo in the mid - west of the Connacht Province and Co. Dublin in the north - east of Southern Leinster.

O Lawler or O Lawlor or Lalor - Irish / Ua Leathlobhair. An Irian Laeghis Ui Laoighis Sept / Family branch of the O More / O Moore / Ui Mordha Sept who were Chiefs and had their territory in Co. Laois  in the mid - north - west of Southern Leinster where they were one of "7 Septs of Leix" and were also in Co. Down in the south - east of the Ulster Province. Especially see - O Lalor.

O Lawn - Irish / Ua Liathain. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Fiachrach Sept / Family branch, who had their territory in Co. Sligo in the north - west of the Connacht Province. Etymologically similar to O Lehane who were in Co. Cork in Southern Munster. Ancestors - *87.Fiachra the original 2nd King of Connacht (Ui Fiachrach), *86.Eochy "Mugmedon" the 124th King of Tara / Ireland.

Lawrence or Laurence, English origins. They have been in Ireland since the Mid - 17th Century AD. See also St. Laurence.

O Lawry. A Sept / Family branch, who had their territory and were Chiefs in Co. Down in the south - east of the Ulster Province.

Lawson. English origins. They have been in the Ulster Province since the early 17th Century AD after the Confiscation of the 3,000,000 acres of the Heremonian Ui Cobhthaigh Dal Cuinn "Northern" Ui Niaill territories and the Foreign non - Catholic Plantations there.

O Lawton or O Loughnane, which see, Irish / Ua Lachtnain - lachtna / grey. They used this English name to anglicize their name in Co. Cork in Southern Munster.

Layd -