Donnchadh's a Gaelic male name. It's reputed to mean "Brown Warrior" (from gaelic donn - brown, cath - battle?) Also written as Donnchad, Donncha, Donnacha, Donnchadha and Dúnchad. In English it's pronounced "Donn-ah" or "Donn-a-ha". Modern versions include (in Ireland) Donagh, Donough, Donogh and (in Scotland) Duncan. Also anglicised as Denis and Dionysius. The surnames McDonagh and O'Donoghue among others are derived from the given name (In Gaelic: Mac - son of, Ó - of the family of)… (More on Donnchadh)