noun
San'yōdō (historical province)
Historical term for one of the old provinces of Japan, roughly corresponding to the modern San'yō region along the Seto Inland Sea.
See also: 山陽地方
山陽道は、古代の行政区画の一つです。
San'yōdō is one of the ancient administrative divisions.
山陽地方 is the modern geographical region, while 山陽道 is the historical province name.
From 山陽 (San'yō, 'sunny side of the mountain') + 道 (dō, 'circuit, province'). The name refers to the region on the southern, sunny side of the Chūgoku mountains.