McCormick is a family name that originated in Ireland and Scotland. Spelling variations: Cormack, MacCormack, McCormack, McCormick, MacCormick, Cormac, Cormach, Cormich and Cormiche. It comes from the first name of the original bearer. A person whose father was named Cormac would identify as Mc (i.e. "son of") Cormac; the combination was continued as the family name by subsequent generations.
Cormac is translated literally as "Charioteer, Warrior". The name was a very popular choice of names by parents in medieval times: this was due to the influences of the Saint of the same name. Saint Cormac was the first Bishop of Cashel an important diocese in the south of Ireland. Cashel was also the King of Munster and responsible for a famous book of Psalms, the Cashel Psalter, he died in battle in AD 908. In those days the McCormack was the name of a powerful Sept (Clan or Family) in the county of Longford.
In 1576, 1598 and 1600, MacCormicks are recorded as leading gentry in County Cork and one, of Muskerry, was influential enough to raise a large force to assist Desmond in the Elizabethan wars. The Annals of the Four Masters record the deaths of several prominent MacCormicks of County Fermanagh; the last of these died in 1431.
Another possible derivation of the name is that it comes from the gaelic Mac Cormaic which comes from corb and mac meaning "Ravenson".