McGillicuddy  McGillicuddy ( or "") is a surname of Irish origin. A variant form of the name is Mac Giolla Mhochuda. Other Anglicised forms of "Mac Giolla Chuda" include "MacGillacuddy", "MacGillecuddy", "MacGillycuddy", "MacIllicuddy", "MacElcuddy", and "MacElhuddy". The female unmarried variation of the name in Irish is ', and the married female version of the name is '. The MacGillycuddy clan were a sept of the O'Sullivans. The family did not adopt this surname until the 1500. Notable people with the surname include:    Fictional characters: