The Morini (Gaulish: 'sea folk, sailors') were a Belgic coastal tribe dwelling in the modern Pas de Calais region, around present-day Boulogne-sur-Mer, during the Iron Age and the Roman period. They are mentioned as Morini by Caesar (mid-1st c. BC) and Pliny (1st c. AD), Morinoì (Μορινοὶ) by Strabo (early 1st c. AD), Morinos by Pomponius Mela (mid-1st c. AD) and Tacitus (early 2nd c. AD), Morinō̃n (Μορινω̃ν) by Ptolemy (2nd c. AD), Mōrínous (Μωρίνους; acc.) by Cassius Dio (3rd c. AD), and as Morinorum (gen.) in the Notitia Dignitatum (5th c. AD). The Gaulish ethnonym Morini (sing. Morinos) literally means 'those of the sea', that is to say the 'sea folk' or the 'sailors'. It stems from Proto-Celtic *mori ('sea'; cf. Old Irish muir, Middle Welsh mor 'sea'), itself from Proto-Indo-European *mori ('sea, standing water'; cf. Lat. mare 'sea', OHG mari 'sea, lake', Osset. mal 'standing water'). Drawing on earlier traditions, the Morini were poetically called by Virgil the "remotest people of mankind" (extremique hominum Morini). The Morini lived south of the Menapii, the river Aa bordering the two tribes from the coast to the east of Saint Omer. There, the frontier turned southwards to meet the river Leie up to Merville, at the one-time territory of the Atrebates. South of their territory, they were separated from the Ambiani by the Canche river. Strabo (early 1st c. AD) describes the country of the Morini as being on the sea, close to the Menapii, and covered by part of a large forest with low thorny trees and shrubs. He also reports that before Roman conquest, the Morini and their neighbours in these forests "fixed stakes in various places, and then retreated with their whole families into the recesses of the forest, to small islands surrounded by marshes. During the rainy season these proved secure hiding-places, but in times of drought they were easily taken." During the Roman period, their capital was known as Tervanna (or Tarvanna). The modern town of Thérouanne is located farther to the south.