A microphone designed to be in physical contact with the object producing sound. A contact mic receives and derives its audio signal from mechanical vibrations instead of airborne sound waves. These are sometimes called “piezo” or “transducer” mics, but “contact mic” is the most accepted name.
Contact mics are sometimes confused with PZM microphones because they too are generally affixed to a surface, however PZMs work from air vibrations and thus shouldn’t be considered contact mics.