| Background: The name Duffy or O'Duffy is widespread in Ireland: it is among the fifty commonest surnames; standing first in the list for Co. Monaghan, it is also very numerous in north connacht. It is found in Munster to some extent but there is often takes the form Duhig, while in parts of Donegal it has become Doohey and Dowey. These variants arose from local pronunciations of the Irish O Dubhthaigh, a surname in which the root word is dubh (black).
Variations: O'Duffy, Duffy, Duhig, Dowey.
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Discussion of this family is welcomed.