Patronymic was used by illegitimate royal children who were acknowledged as such by their fathers. The use of "Mac" in some form was prevalent in Scottish Gaelic, Irish and Manx, in all of which it denotes "son". "Mc" is also a frequent anglicisation in both Scotland and Ireland. In Ireland, the forms "Mag" and "M'" are encountered. The prefix "Mac" is used to form a patronym, such as "Mac Coinnich" – or the anglicized 'Mackenzie' – son of Coinneach/Kenneth. The female equivalent of "Mac" is "Nic", condensed from "nighean mhic" (in Scottish Gaelic) or "iníon mhic" (in Irish), both meaning daughter.
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