Dumnonii the origin of the interpretation of Dumnonii as "deep valley dwellers" from his understanding of the Welsh of his time. John Rhys later theorized that the tribal name was derived from the name of a goddess, "Domnu", probably meaning "the goddess of the deep". The proto-Celtic root *dubno- or *dumno- meaning "the deep" or "the earth" (or alternatively meaning "dark" or "gloomy") appears in personal names such as Dumnorix and Dubnovellaunus. Another group with a similar name but with no known links were the Fir Domnann of Connacht. The Roman name of the town of Exeter, "Isca Dumnoniorum" ("Isca of
Insula (Roman city) forum around which the most important public buildings would be sited. Insula (Roman city) An insula (Latin for "island") is a city block in an ancient Roman city plan, i.e. one that is surrounded by four streets. The term was also used for apartment buildings that took up an entire city block. A standard Roman city plan was based on a grid of orthogonal streets and was probably founded on the ancient Greek model of Hippodamus and was used when new cities were established, e.g. in Roman coloniae. The main streets of each city would be the Decumanus Maximus (east–west-oriented)