Family name origins & meanings
- Irish (Counties Fermanagh, Leitrim, and Roscommon) : reduced Anglicized form of Gaelic Ó Dúnáin ‘descendant of Dúnán’, which is a pet form of a longer name beginning with dun ‘fortress’.
- Irish (Counties Fermanagh, Leitrim, and Roscommon) : reduced Anglicized form of Gaelic Ó Donnáin (see Donnan).