McCaughan is a surname of Irish origin, deriving from the Gaelic Mac Eacháin, which translates as son of Eachán. Eachán itself is a diminutive of each, the Gaelic word for horse, so the surname originally denoted a descendant of a person associated with horses or a horse‑related occupation.
The name is predominantly found in Ulster, with early records concentrated in Counties Antrim, Derry, Down and Tyrone. In Ulster Church Registers the surname occurs under variants such as Mc Caughan, Mc Coughan and Mc Caghan. It has also been documented in the 17th‑century Hearth Money Rolls of County Tyrone, where it appears as MacCahee or MacCaughey around 1650, during the reign of Oliver Cromwell.
Traditional Irish family names are often patronymic, prefixed by Mac (meaning “son of”) or O (meaning “grandson of” or “descendant of”). The surname McCaughan follows this pattern, indicating descent from an ancestor named Eachán. Some families altered the spelling to Mac Caughey, an Anglicised form of the cognate Ulster name Mac Eachaidh, also meaning “son of the Horseman”.
In the 18th and 19th centuries records show McCaghan witnessing a christening in Magheralin, County Down, in 1784, and a birth of a McCaughan in Dervock, County Antrim, in 1865. During the Great Famine, a family bearing the name Mc Caughen emigrated from Belfast on the ship Monterey in April 1847, illustrating the dispersion of the name beyond Ireland.
While the core meaning remains linked to horsesmanship, the surname has given rise to several alternative spellings, including MacCahan, McCahan, McCann, MacAghon, Caghan, Cahan, Kahan, Keaghan, McKeegan and others. These variations stem from phonetic interpretation and regional accents, with certain spellings such as Kahan or McKeegan reflecting non‑Irish origins or distinct Gaelic roots like Mac Catháin.
In contemporary times, the surname remains most common within Ireland, especially in Ulster and to a lesser extent in Munster. Outside of Ireland it appears in the Irish diaspora, notably in the United States, Canada and Australia, though its prevalence there is comparatively limited. The distribution of the surname and its variants offers genealogical insight into migration patterns and linguistic evolution.