The definition of seismic is relating to or subject to earthquakes or man-made tremors.(adjective)
An example of something seismic is the movement of land during an earthquake; seismic movement.
See seismic in Webster's New World College Dictionary
Origin: < Gr seismos, earthquake < seiein, to shake < IE base *twei-, to excite, shake, shock > Sans tviṣ-, to be excited, sparkle
See seismic in American Heritage Dictionary 4
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