Ó Crotaigh
Ó CROTAIGH—I—O Crotty, Crotty; 'descendant of Crotach' (hunch-backed); the name of a Waterford family, said to be a branch of the O'Briens of Thomond, who were formerly seated in the neighbourhood of Lismore and are now found in many parts of Munster.
Alphabetical Index to Irish Surnames