Word Study
Seismograph
CIDE DICTIONARY
Seismograph, n. [Gr. an earthquake + -graph.].
An apparatus for registering the shocks and undulatory motions of earthquakes. [1913 Webster]
OXFORD DICTIONARY
Seismograph, n. an instrument that records the force, direction, etc., of earthquakes.
Derivative
seismographic adj. seismographical adj.
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