Anglicized form of Gaelic Domhnall. The final -d of the Anglicized form derives partly from misinterpretation by English speakers of the Gaelic pronunciation, and partly from association with Germanic-origin names such as Ronald. This name is strongly associated with clan Macdonald, the clan of the medieval Lords of the Isles, but is now also widely used by families with no Scottish connections.
English, Welsh, and Irish: from the personal name Piers, the usual Norman vernacular form of Peter. In Wales this represents a patronymic ap Piers. In Ireland it represents a reduced Anglicized form of Gaelic Mac Piarais ‘son of Piaras’, a Gaelicized form of Piers.