nouninformal, dialect Music
Any of various stringed instruments having a bass or droning tone; (now) specifically a type of folk instrument consisting of a monochord stretched on a long pole over a resonating bladder or drum, typically played with a stick or bow to produce a bass note or rhythm, and often having other percussion instruments attached.
In earliest use applied to a bass violin or violoncello.
Late 18th century; earliest use found in Samuel Pegge (1733–1800), antiquary and writer. Apparently from bum + bass.