It is composed of the elements donn, meaning "brown" or "dark" from Donn a Gaelic God; and chadh, meaning "chief" or "noble".
[2][3][4] The name is also written as Donnchad, Donncha, Donnacha, Donnchadha and Dúnchad.
Modern versions include (in Ireland) Donnacha, Donagh, Donough, Donogh and (in Scotland) Duncan.
The Irish surnames Donough, McDonagh, McDonough, O'Donoghue and Dunphy among others are derived from the given name (In Gaelic: Mac – son of, Ó – of the family of).
[citation needed] Notable people with the name include: