mechanical musical instrument 1

General term used to describe all self-playing musical instruments (although certain types of pneumatic instruments with sophisticated expression capabilities-large orchestrions, pipe organs, and reproducing pianos, for example-were never designated as such). See automatic musical instrument. 2. Self-playing musical instrument, especially one that is powered by a hand crank, a spring, a weight drive, or other clockwork mechanism (as opposed to electrically-driven instruments, most of which were originally designated as automatic rather than mechanical).