relating to earthquakes or other vibrations of the earth and its crust:after a few days of seismic activity the volcanic eruption started
relating to or denoting geological surveying methods involving vibrations produced artificially by explosions:seismic data show the deep structure of rift systems
of enormous proportions or effect:there are seismic pressures threatening American society
seismical
adjective
seismically
adverb
[as submodifier]:this region is the most seismically active in North America
