MacLoughlin, O’Loughlin, ó Maoilsheachlainn
A Gaelic surname meaning descendant of Maolsheachlainn (servant of St. Secundinus), the Ard-Rí who was dethroned by Brian Boru. A sept of Clann Cholmain who were Kings of Meath prior to the Cambro-Norman invasion. The sept described as the O’Melaghlens were confined to the barony of Clonlonan in Westmeath. In its anglicised form of MacLoughlin difficult to distinguish from MacLaughlin. Sometimes an anglicisation of ó Lachtnáin. In 1890 McLoughlin was numerous in Sligo, Leitrim and Fermanagh, it was also to be found in Dublin. The estimated number of bearers was 7,616. In 1890 Loughlin was principally found in Leitrim, Dublin, and Kilkenny, and the estimated number of bearers was 1,750. Laughlin was principally found in Tyrone and Antrim, and the estimated number of bearers was 630. In the United States McLoughlin is the 7,523rd most numerous surname with an estimated 2,750 bearers.