What instrument did Cliff Burton play in Metallica?

Cliff Burton played bass guitar in Metallica.

Burton joined Metallica in 1982 after the band saw him perform with the California group Trauma. He replaced the band's original bassist, Ron McGovney, and became a defining part of Metallica's early sound. His playing combined heavy-metal power with classical and jazz influences, and he was known for using distortion, wah-wah, and other effects on the bass.

Burton played on Metallica's first three studio albums: Kill 'Em All, Ride the Lightning, and Master of Puppets. His prominent bass work is especially clear in the instrumental “Orion” and in the opening passage of “For Whom the Bell Tolls,” which listeners sometimes mistake for a guitar part.

Burton died in a tour-bus accident near Dörarp, Sweden, on September 27, 1986, while Metallica was touring in support of Master of Puppets. Jason Newsted became his replacement. The wording “bass guitar” is the standard answer, even though Burton also used effects that gave his instrument an unusually lead-like sound.