A patronymic surname is one that is derived from a person’s father’s first name. At some point in history many patronymic surnames were adopted as permanent, inherited surnames, and so they survive today. Gaelic patronymic surnames from Ireland and Scotland have several unique features as well as a distinctive history in their evolution into modern surnames.

There is a persistent myth about Scottish and Irish surnames that begin with the prefix Mac- or Mc-. This myth is that Mac- (as in MacDonald – son of Donald) designates a Scottish and Protestant heritage, where as Mc- (as in McCormick – son of Cormac) denotes an Irish Catholic family name. In truth, there is no difference between these two prefixes, and they can be either Irish or Scottish in origin and spelled different ways and with either prefix, even within the same family.

Mac- and Mc- come from the Gaelic word “meic,” meaning “son of.” Meic was contracted or abbreviated in various other ways, including mic, Mhic M’c, M’, Mcc, and Mc with two dots under the c. Such a large number of Irish names carried the mic prefix that it became an ethnic slur for the Irish people in general: “micks.” Some names beginning with Mc- or Mac- are not strictly patronymic, but are the professional or descriptive names of the father. Thus MacMaster denotes the “son of a master or cleric”, Macpherson means “son of the parson,” MacWard is the “son of a bard,” MacKinzie signifies “son of the fair one,” MacDuff means “son of the dark one,” and McDowell indicates a “son of the dark stranger.”

Middle names did not come into use in either Scotland or Ireland until after the 16th century. In the old parish registers of Scotland in the 17th and 18th centuries, the Gaelic term “nighean mhic,” meaning “daughter of,” could also be found as part of patronymic surnames. This was abbreviated variously as Nc, N’, Nee, nighean and inghean uí. Thus, a name like NcFarlane (meaning daughter of Parthalán, or Bartholomew) could be found in the records. These Nc- names essentially went out of use after the 1700s. Similarly, the abbreviation Vc- could be found in the old records. This referred to the “grandson of” a male ancestor. Thus, Dugall McDonald VcEan was Dugall, son of Donald, grandson of Ean.

In contrast to Mc- and Mac-, found in both Ireland and Scotland, the prefix O’ is unique to Ireland. It is derived from the Gaelic word “ua,” also abbreviated as uí or Ó, meaning “grandson of.” Thus any name beginning with O’ is without question an Irish patronymic. The O’ surnames began as early as the 11th century in Ireland, much earlier than the Mc/Mac surnames. At first the upper classes took surnames in Ireland, followed gradually by the lower classes and peasants, who had adopted them by the 16th century. Examples of these surnames are O’Sullivan, O’Connor, O’Brien, and O’Leary.

The prefix Fitz- is also found in Irish surnames. This term is Latin for “son of,” and was brought to Ireland by the Norman invaders in 1066. Examples of names using this patronymic prefix are Fitzpatrick, Fitzgerald, and Fitzsimmons. Other Irish names derived from the French/Norman invasion are Burke, Costello, Nagle, Nugent, Power, Roche, and Walsh. Despite their foreign origins, these are now seen as Irish surnames.

In the 1600s the English invaded Ireland under King William of Orange, and as a result Irish surnames suffered a “forced anglicization” by the English. Gaelic spellings were changed and patronymic prefixes were dropped from surnames. Thus the Gaelic MacGabhann and O’Gabhan (meaning “son of the smith”) were anglicized to McGowan, or translated directly to Smith. In the 1800s many Irish families put the prefixes back on their names again, but some never did. Thus, when researching your family name be aware that a name like Connor could have once been O’Connor.