Cróc
CRÓC—VIII—Croc, Crok, Croke, Croake; Crooke, Crooks, etc.; 'son of Croc' (old Norse Krokr, a personal name which appears more than once in Domesday Book and was borne by holders of land in the time of Edward the Confessor and by tenants-in-chief and undertenants at the time of the survey). The Crokes settled at an early period in Kilkenny, Tipperary and Cork. Crooke represents a later immigration, and is more widespread.
Alphabetical Index to Irish Surnames