<Tr> <Th> Mongolian </Th> <Td> адъяа ad'yaa </Td> <Td> сумъяа sum'yaa </Td> <Td> ангараг angarag </Td> <Td> буд bud </Td> <Td> бархабадь barhabad' </Td> <Td> сугар sugar </Td> <Td> санчир sanchir </Td> </Tr> <P> The East Asian naming system for the days of the week closely parallels that of the Latin system and is ordered after the "Seven Luminaries" (七曜 qī yào), which consists of the Sun, Moon and the five planets visible to the naked eye . </P> <P> The Chinese seem to have adopted the seven - day week from the Hellenistic system by the 4th century, although by which route is not entirely clear . It was again transmitted to China in the 8th century by Manichaeans, via the country of Kang (a Central Asian polity near Samarkand). The 4th - century date, according to the Cihai encyclopedia, is due to a reference to Fan Ning (範 寧 / 范 宁), an astrologer of the Jin Dynasty . The renewed adoption from Manichaeans in the 8th century (Tang Dynasty) is documented with the writings of the Chinese Buddhist monk Yi Jing and the Ceylonese Buddhist monk Bu Kong . </P> <P> The Chinese transliteration of the planetary system was soon brought to Japan by the Japanese monk Kobo Daishi; surviving diaries of the Japanese statesman Fujiwara Michinaga show the seven day system in use in Heian Period Japan as early as 1007 . In Japan, the seven day system was kept in use (for astrological purposes) until its promotion to a full - fledged (Western - style) calendrical basis during the Meiji era . In China, with the founding of the Republic of China in 1911, Monday through Saturday in China are now named after the luminaries implicitly with the numbers . </P>

When were the days of the week given names