Temperment – the spacing of keys within an octave.
Octave Stretching – how far apart the notes of an octave are from pure.
Pin Block – the block of wood that holds the tuning pins in place.
Sounding Board – the large diaphragm used to expand the surface area that vibrates, translating into more volume for your ears to hear.
A-440 Tuning – the A above middle C tuned to 440 cycles per second.