Downie or Downey is a surname. There appears to be a number of sources of the Downie/Downey surname in Scotland and Ireland, with the intermittent mix in Ulster. The spelling of the surname as Downie is almost unique to Scotland with minor instances in Northern Ireland (Antrim). The following information on the origins of the name are taken from.[1]
There are Dounie/Doune/Downie place names or hill forts or Dun in most parishes in Scotland, including Aberdeen, Angus, Stirling, Perth, Inverness and the Isle of Lewis. The name may derive from any of these, or from the Barony of Downie in Angus.
It is also a derivative of the Gaelic Mac Gille/Maol Domhnaich or McAldonich "son of the servant of the Lord (Sunday)" which both are anglicised to Macgildownie, Mcildownie and Gildownie (and many variations) to Downie, mainly in the parishes of Argyll, western Perth and Inverness.
O’Dunadhaigh is a person identified with a fort or Dun. This surname is found mostly in County Galway, South West Cork and Leinster. The surname is often anglicised to Downey. Mac Dunadhaigh, identified with a fort or Dun, is the surname of an old Galway family.
The first name such as Maol Domhnaich, or Muldonich meaning the "Lord's Devotee" have been used in Scotland and may have been the precursors to the Mac variations.
Notable people with the surname Downie include: