Kavanagh (surname) Kavanagh (surname) Kavanagh or Kavanaugh is a surname of Irish origin, Caomhánach in Irish Gaelic. It is properly "Mac Murchadha Caomhánach" (an example of an Irish agnomen; see "Ó Catharnaigh Sionnach" or Fox of Fir Teathbha), but is often now rendered 'Caomhánach' or rarely 'Ó Caomhánaigh'. "Kavanagh" and "Kavanaugh" are anglicised variations of the Irish Gaelic surname Caomhánach (Cʌoṁʌ̃nʌċ in traditional Gaelic script). The surname was first assumed by Domhnall Caomhánach (the eldest son of the 12th century King of Leinster, Diarmait Mac Murchada) in Ireland. A considerable number of anglicised variations of Caomhánach exist, with some of the most
Mac and Mc together in print two publications on filing rules, one covering that "word-by-word" convention, and another prepared in 1980 that is "letter-by-letter". A 1998 book attributes the changes to the rules to computer informatics, and notes the Mac/Mc change as its first example. 1982's "Scottish Roots", a guide for family history researchers, warns that older Scottish records do not in fact follow this convention, unlike contemporary telephone directories. A 2001 book of "New York Times" theatre reviews sorts Mc names as if spelled Mac. A 2002 official document for the State of Vermont recommends explicitly no special treatment for Mac and Mc.