Home›Browse›T›tuning hammertuning hammerOur editors are putting together more complete content — check back in about 20 minutestuning hammertuning hammer — nounnoun1. a tool used to tighten or loosen the tuning pins of a piano1.nounDefinitiona tool used to tighten or loosen the tuning pins of a pianoExampleThe technician used a tuning hammer to adjust the piano's pitch.