Ó Floinn is an Irish surname, historically borne by the descendants of a Norse-Gaelic kindred. It is the original Gaelic form of the better-known anglicized surname Flynn, both derived from the Old Irish personal name or byname Flann, meaning "blood red." The prefix Ó denotes "grandson" or "male descendant of," making Ó Floinn essentially the patronymic "descendant of Flann." Etymology The root flann referred to a ruddy complexion or a bloody-red color in early Irish. This byname was favored among early medieval Irish kings and warriors, suggesting a person of intense or fiery character. The eponymous ancestor Flann itself was not the founder of any single clan but a personal name held by several historical figures, including a 9th-century high king of Ireland. Historical and Cultural Context Closely related are the variant surnames Flanagan, Flanagon, and Ó Flannagáin, which come from a diminutive form, Flannagán—"little red one." These names historically belong to distinct but related Irish septs, primarily from the province of Ulster. Over centuries, the native Irish spellings gave way to anglicized forms, especially after the collapse of the Gaelic order in the 17th century. Notable bearers of the surname include Críostóir Ó Floinn (1927–2023), an Irish poet, writer, and academic who contributed to the preservation and translation of Gaelic literature. Another is Raghnall Ó Floinn (died 2024), an eminent art historian and former Head of Collections at the National Museum of Ireland, known for his expertise on early medieval Irish metalwork and other artifacts. Geographical and Genealogical Notes The Ó Floinn domain in medieval Ireland centered around the modern county of Mayo in Connacht, where the surname remains concentrated today. Non-Gaelic records often show O'Flynn as the dominant spelling after emigration to English-speaking countries, especially in the United States, where large clusters settled during the post-Famine period. Meaning: Descendant of the "blood red" one Origin: Irish Gaelic (patronymic) Type: Surname Usage: Ireland, Irish diaspora