The Chinese word "亚瑟" is formed through a process of phonetic translation, specifically as a transliteration of the English name "Arthur". The characters were chosen not for their individual meanings (which are "inferior/second" for 亚 and a type of ancient plucked instrument for 瑟), but purely for how closely their sounds in Mandarin (yà sè) approximate the sounds of the foreign name. It is a conventional, established sound-matching used to represent that specific foreign entity in Chinese writing.