Murphy is an Irish surname meaning "Sea Warrior."
[3] According to historian C. Thomas Cairney, the O'Murphys were one of the chiefly families of the Uí Ceinnselaig who in turn were a tribe from the Dumnonii or Laigin who were the third wave of Celts to settle in Ireland during the first century BC.
[4] The O'Murphys as one of the chiefly families of the Uí Ceinnselaig is supported by John O'Hart in his 1892 Irish Pedigrees; or, The Origin and Stem of The Irish Nation.
[5] Murchadh is reported to have been gripped with a boiling awful rage, an extreme elevation and greatness of spirit and intellect when he joined the middle of the action and prepared to assail the foreign invaders, the Danes, after they had repulsed the Dal gCais.
A gallantry and championship bird rose inside him and fluttered above his head and on his breath.