The origin of this name is still today quite uncertain. The theories include: 1) From the Gaelic element "dí", meaning "without". 2) From the Gaelic "airmit", meaning "injunction". 3) From the Gaelic "airmit", meaning "envy". The Scottish Gaelic form of the name is Diarmad; Anglicized forms of this name include Diarmid and Dermid. Saint Diarmaid was an Irish bishop of Armagh known for his learning. He was named bishop in 834 but was driven from his see by a usurper, Forau. Diarmaid went to Connacht, where he ruled as primate. During his reign, Norsemen destroyed churches inArmagh in 841.