McLaughlin (surname) McLaughlin (surname) M(a)cLaughlin is the most common English form of "Mac Lochlainn", a masculine surname of Irish origin. The feminine form of the surname is "Nic Lochlainn". The literal meaning of the name is "son of "Lochlann"". Note that "Mc" is simply a contraction of "Mac", which is also (albeit rarely) truncated to "M' ". Thus, "MacLaughlin", "McLaughlin" and "M'Laughlin" are the same Anglicism, the latter two merely contractions of the first. The original surname Mac/Nic Lochlainn was borne by a family of Cenél nEógain, a branch of the historic northern O'Neill dynasty, reputedly founded by Niall Noígíallach. This family
Mac and Mc together A 2007 book in its tenth edition states that "most library catalogs" sort Mac and Mc names as if spelled M-a-c. Among the guides which generally recommend separating Mac and Mc so that names will be sorted as they are spelled are ISO 999, The Chicago Manual of Style, "Butcher's Copy-editing: The Cambridge Handbook for Editors, Copy-editors and Proofreaders", "The New York Times Manual of Style and Usage", and "The SBL Handbook of Style". Mac and Mc together A convention of sorting names with the Scottish and Irish patronymic prefixes Mac and Mc together persists in library science and archival