Mac Lochlainn
Mac LOCHLAINN—V—MacLochlin, MacLoghlin, MacLoughlin, Loughlin, &c, (Loftus); 'son of Lochlainn' (a name of Norse origin); the name of the senior branch of the northern Ui Neill. Before the 13th century, they were the most powerful family in Ulster. They were seated in Inishowen, where the name is still common. A branch of this family settled in Mayo in the 17th century. It would appear that there was also a family of the name in Co. Leitrim, who were followers of the O'Rourkes. This surname is to be distinguished from Ó Maoilsheachlainn (which see), which is now also anglicised MacLoughlin. See Mag Lochlainn.
Alphabetical Index to Irish Surnames