It is the name of a Japanese musical instrument, consisting of three strings. It is also called samisén. It is a derivation of the similar Chinese instrument, called sanxián.
SHAMISN Japanese musical instrument similar to a banjo but square and flat box. It comes from a Chinese instrument called sanxian (three strings) that appeared in the 13th century during the Yuan dynasty. From there it passed to Ryukyu (Okinawa) and then to all of Japan.