Ó Nuallacháin
Ó NUALLACHÁIN—I—O Nolloghaine, (Nolan); 'descendant of Uallachán' (diminutive of uallach, proud). The form of this surname is peculiar, being really the genitive plural of Ó hUallacháin, which see. With names of women it is quite regular, e.g., Bríghid Ni Uallacháin.
Alphabetical Index to Irish Surnames