Tags: Name, Surname.
The name Dennehy is principally associated with Irish counties Cork and Kerry. In Cork the name is most common in the Duhallow area around the Blackwater river. The original form in Irish is Ó Duineachdha meaning descendant of Duineachaidh. Duineachaidh was chieftain of a small tribe in north-western Co. Waterford on the border of Co. Cork who participated in the battles against the Danes in Limerick in 934. The name goes back to the 11th century recorded in the Battle of Dublin.