SEISMOGRAPH
seismograph
(noun) a measuring instrument for detecting and measuring the intensity and direction and duration of movements of the ground (as an earthquake)
Source: WordNet® 3.1
Etymology
Noun
seismograph (plural seismographs)
An instrument that automatically detects and records the intensity, direction and duration of earthquakes and similar events.
Source: Wiktionary
Seis"mo*graph, n. Etym: [Gr. -graph.] (Physics)
Definition: An apparatus for registering the shocks and undulatory motions
of earthquakes.
Source: Webster’s Unabridged Dictionary 1913 Edition