Doohey, Dowey, Dowie, Duffey, Duffie, Duhig, O’ Duffy, Ó Dubhthaigh
The name Duffy is an Anglicisation of the Irish Ó Dubhthaigh, from the Gaelic “Dubhthach” meaning ‘the dark one’. There were originally several septs of Ó Dubhthaighs from which the modern Duffy name, and its variations, are descended, located in counties Donegal, Monaghan and Roscommon. Many of the Duffy clan historically had strong links with the church, and produced a succession of distinguished abbots and bishops. Duffy is now the most common name in Co. Monaghan.