The top 100 Irish last names explained

Find out more about your Irish roots and where your family name hails from

(O) Lemon - Lenna  Ó Leannáin (possibly from leann, a cloak or mantle; leanán, paramour, has also been suggested). This is the name of several distinct septs located respectively in Co.s Cork, Fermanagh, and Galway. The last named is of the Sodhan pre-Gaelic stock. The Fermanagh family were erenaghs of Lisgoole. Ó Leannáin is also used as a synonym of Lineen (Ó Luinín), another Fermanagh erenagh family. Further confusion arises from the fact that these have been widely changed to the English name Leonard.

Mac Loughlin - Mac Lochlainn (from a Norse personal name). Of Inishowen. A senior branch of the Northern Uí Néill. They lost their early importance as a leading sept of Tirconnell in the thirteenth century, but are still very numerous in their original homeland-Co.s Donegal and Derry-where their name is usually spelt MacLaughlin; MacLoughlin, also numerous, is more widespread. Minor septs in Connacht were akin to the MacDermota and the O’Connors.

Mac Mahon - Mac Mathghamhna mod. Mac Mathúna (mathghamhan, bear) Thename of two septs, both of importance. That of Thomond descends from Mahon O’Brien, grandson of Brian Ború. MacMahon is now the most numerous name in Co. Clare. In later times the majority of the many of the name were from the Co. Monaghan, where McMahons are numerous today, though less so in Thomond.

(O) Malley - Mailey  Ó Máille. (meall, peasant). A branch of the Cenél Eoghain located in Tyrone where their territory was known as ‘O’Mellan’s Country’. They were hereditary keepers of the Bell of St. Patrick.

O’Meara - Mara  Ó Meadhra (meadhar, merry). This well-known sept, which has produced many distinguished men and women, gave its name to the village of Toomevara, which locates their homeland. This one of the few O names from which the prefix was never very widely dropped.

Molloy - Mulloy  Ó Maolmmhuaidh. (The adjective muadh) denotes bit and soft as well noble). An important sept of Fercal in mid-Leister. Molly is an anglicized form of Ó Maolaoidh. Apart from five variant spellings, such as Maloy and Mulloy, Molloy has been officially recorded as synonym of Mulvogue (Connacht), Logue (Co. Donegal), Mullock (Offaly), Mulvihill (Kerry), and Slowey (Co. Monaghan) while Maloy has been used for MacCloy in Co. Derry.

(O) Moran - Apart from MacMorran of Fermanagh, which has inevitably been changed to Moran, there are a number of distinct septs of Ó Moráin and Ó Moghrain whose name is anglicized Moran. Four of these are of Connacht-in which province the name is much more numerous  than elsewhere-originally located (a) at Elphin (akin to the O’Connors), (b) in Co. Leitrim (of the Muinitir Eolais), (c) in. Co. Mayo at Ardanee, (d) in Co. Galway, a minor branch of the Uí Maine. The Leitrim families are also called Morahan, as is the fifth to be enumerated, viz. that of Offaly, where Morrin is a synonym.

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