The shamisen , also known as sangen or samisen (all meaning "three strings"), is a three-stringed traditional Japanese musical instrument derived from the Chinese instrument sanxian. It is played with a plectrum called a bachi.

A plectrum is a small flat tool used for plucking or strumming of a stringed instrument. For hand-held instruments such as guitars and mandolins, the plectrum is often called a pick and is held as a separate tool in the player's hand. In harpsichords, the plectra are attached to the jack mechanism.