seismometer

noun

1. a seismograph equipped for measuring the direction, intensity, and duration of earthquakes by measuring the actual movement of the ground.

n.“instrument for measuring the intensity and motion of earthquakes,” 1841, from seismo- + -meter. Originally different from a seismograph but now practically the same thing.

1. A detecting device that receives seismic impulses. It is the detecting component of a seismograph. See more at seismograph.