由来と歴史

Anglicisation of the Irish Gaelic 'O Braonain', meaning 'descendant of Braonan', where 'Braonan' is a diminutive of 'braon' meaning 'moisture', 'drop', or 'sorrow'. Several O'Brennan septs existed across Ireland, the most important being based in County Kilkenny, where they were lords of Idough, and in County Fermanagh. Brennan is also sometimes an anglicisation of 'O Branain' (descendant of Branach, meaning 'raven'). The name is broadly distributed across Munster and Leinster and is among the most common surnames in County Kilkenny.