Armorica

n. literary and ancient name of northwest France; ancient name of Brittany

Armorica or Aremorica is the name given in ancient times to the part of Gaul that includes the Brittany peninsula and the territory between the Seine and Loire rivers, extending inland to an indeterminate point and down the Atlantic coast. The toponym is based on the Gaulish phrase are mori "on/at [the] sea", made into the Gaulish place name Aremorica 'Place by the Sea'. In Breton (which with Welsh and Cornish are the living related languages of Gaulish), 'on [the] sea' is war vor (Welsh ar for), though the older form arvor is used to refer to the coastal regions of Brittany, in contrast to argoad (ar 'on/at', coad 'forest' [Welsh ar goed ('coed' forest)] for the inland regions. This modern usage suggests that the Romans first contacted coastal people in this region and assumed that the regional name Aremorica referred to the whole area, both seashore and inland.
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adj. armorican, of Brittany, Breton

n. Brittany, region in northwestern France (History)

Ancient name ‘on the sea’ in the Breton language, often confused with Amonica in Northern Wales. Geoffrey of Monmouth made this error, placing the events of King Arthur on the continent rather than in Wales, where they make more sense.