The Gaelic surname Mac Somhairle means "son of Somhairle". The personal name Somhairle is a Gaelicised form of the Old Norse Sumarliðr and Sumarliði. The Old Norse Sumarliðr is composed of the elements sumar ("summer") and liðr ("seafarer"). As such, Sumarliðr and Sumarliði can be taken to mean "summer warrior", "summer seafarer". Anglicised forms of Mac Somhairle include: MacSorley, McSorley, Sorley, and Sorlie. Many settled in Ulster, hired as Gallowglass for Gaelic Kingdoms.