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 example has been taken as representative of a possible paradigm. A book on filing rules from 1918 gives an example showing Mc and M' treated as abbreviations, i.e. for Mac, and ordered as if in the expanded version; and a similar book from 1922 makes the rule one of a number that apply also to St. (Saint) and Mrs. (Mistress). A 1938 book that is a comparative study of cataloguing in various British libraries regarded Mac + Mc + M' sorting as an example of achieved "standardisation" in alphabetisation. It gave further examples where, it argued, such standardisation would be