An instrument for automatically detecting and recording the intensity, direction, and duration of a movement of the ground, especially of an earthquake.
seis·mogra·pher (sīz-mŏgrə-fər) n.
seis′mo·graphic (-grăfĭk), seis′mo·graphi·cal (-ĭ-kəl) adj.
(click for a larger image)seismograph
data relating to the 1994 earthquake in Northridge, California
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
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