McGuire
An Irish surname from the Gaelic Mag Uidhir, traditionally meaning “son of Odhar,” a byname linked with swarthy or dun coloring.
The #521 most common surname in the United States (2010 Census) — about 1 in every 4,800 Americans shares it.
Etymology
McGuire is the anglicized form of Irish Mag Uidhir, also written in older sources as Mac Uibhir or Maguibhir. The name is generally explained as “son of Uidhir/Odhar,” from a Gaelic byname meaning dun-colored, tawny, or swarthy. Some 19th-century writers also tried to connect it with a personal name such as Guaire, but the Irish Gaelic derivation is the standard one in modern scholarship.
History
The surname is strongly associated with County Fermanagh, where the Maguires were a major ruling family. Historical sources also note the name in counties such as Dublin, Cavan, Donegal, Roscommon, and Mayo, reflecting wider Irish spread and later migration. In English-language records it appears in several spellings, including Maguire, MacGuire, and McGuire.
Origin
Regions
Variant spellings
Fun fact
The surname is so closely tied to Fermanagh that the Maguire chiefs became one of the best-known Gaelic dynasties in Ulster.
From the historical record
“and of distinguished ancestors. (See Gregor.) McGUIRE. The son of Guaire or Godfrey. Gmire was a son of Alpin, King of Scotland. McHARD or McHARG. (Welsh, Cor. Br., and Gaelic.) The son of the brave or the handsome. Mac 'Arg. McILDOEY. From Mac, son, giUe, a youth, and dhu, black; the son of the black youth.…”
— An Etymological Dictionary of Family and Christian Names