Segodūnum is an old Celtic place name derived from Proto-Celtic *sego-dūno-, meaning "strong fortress".The Place-Names of Roman Britain, pp. 452-3. A.L.F. Rivet & Colin Smith (1979). Princeton University Press.
It can refer to the following locations: Rodez, Aveyron, former town of the Ruteni in Aquitania Segedunum, Wallsend, England. Suin, Saône-et-Loire Syon Haute-Savoie Würzburg, Bavaria
It may have Germanic counterparts in Swedish Fornsigtuna and Sigtuna, from Proto-Germanic *siga-tūna-, Old Norse Sigtún.Koch, John T. (2020). CELTO-GERMANIC Later Prehistory and Post-Proto-Indo-European vocabulary in the North and West , p. 131Entry Sigtuna in Svenskt ortnamnslexikon. Ed. Mats Wahlberg. Institutet för språk och folkminnen, Uppsala 2003. References