Dunn

Dunn is a surname of English and Scottish origin. It is commonly considered to be topographic, derived from Old English dun, meaning a hill or hill fort, or it may originate from a personal name later extended with a diminutive suffix. The spelling variants include Dunn, Dunne, and Donne, and the name has spread to many English-speaking countries through migration and settlement.

As a place name, Dunn occurs in several countries. In the United States, it designates towns and counties, the best-known example being Dunn, North Carolina. There are also Dunn Counties in multiple states, reflecting the toponymic origin. Other lands have geographic features or communities named Dunn, again tracing to the same root.

In science and statistics, the Dunn index, named after J. C. Dunn, is a measure used to assess the quality of clustering: higher values indicate better separation and compactness of clusters.

In culture and everyday use, the name Dunn appears as a surname carried by many individuals across politics, sports, and the arts, and it also features in various company names and institutions. The term is closely related to its variants, such as Dunne and Donne, and is treated as a family name with broad historical and geographic associations.