Today's name is Duffy. It is the 45th most common name in Ireland.

The Gaelic equivalent is O Dufaigh which means dark or black.

The name Duffy in Ireland is derived from the Gaelic, O'Dubhthaigh, common in Monaghan, Donegal and Roscommon. The name is now very numerous in each of the Provinces with the exception of Munster where the local version Duhig or Doohig is used.