Gahan (surname) Irish language "Mac Gaoithín", meaning "son of "Gaoithín"", although the more common Anglicised form of this Gaelic name is "McGeehan" in Ulster. Gahan (surname) Gahan (and its variant Gahame) is a surname with several different origins. One origin of the surname is from a reduced form of "McGahan", which is in turn an Anglicised form of the Irish language "Mac Eacháin", meaning "son of "Eachán"". Another origin of the name, in Leinster, is from a reduced form of the Irish language "Ó Gaoithin", meaning "descendant of "Gaoithín"". The personal name "Gaoithín" is a diminutive of "gaoth", meaning "wise", or "wind".
Mac and Mc together dropped for some newer computer systems, and the interfiling of Mac and Mc names is an example, according to a 2006 book. There are in fact a number of options. In addition to sorting them under "Mac" and "Mc" respectively or choosing to sort them both under "Mc", it is known for Mc/Mac names to be placed in position before M. This topic has a complicated and disparate history, spread over different continents and relating to different areas of indexing, cataloguing and filing. The idea of a collating sequence itself has evolved, over time, and the "Mac and Mc" together