brain: [OE] Old English brægen came from a Germanic *bragnam. Its rather restricted distribution in modern Germanic languages (apart from English brain there is only Dutch and Frisian brein) suggests that in prehistoric times it may have been limited to the area of North Germany where the Low German dialects were spoken, but it may well have some connection with Greek brekhmós ‘forehead’. [brain etymology, brain origin, 英语词源]