FENNESSY Family History
This very unusual surname recorded in the spellings of Fancy, Fansy, Fennessy, Phinnessy, and Finessy, is of medieval Irish origins. According to our research and to the famous book on Irish surnames by MacLysaght, the surname is mostly found in Counties Cork, Tipperary, and Waterford. The name spelling was originally O'Fionnghusa, or the descendant of the fair and vigourous one, from the Gaelic word "fionn" meaning fair haired or fair skinned, plus "gus" - active or vigourous. This translation is very interesting.