Main Entry: seis·mic

Pronunciation: \ˈsīz-mik, ˈsīs-\

Function: adjective

Etymology: Greek seismos shock, earthquake, from seiein to shake; probably akin to Avestan thwaēshō fear

Date: 1858

1 : of, subject to, or caused by an earthquake; also : of or relating to an earth vibration caused by something else (as an explosion or the impact of a meteorite)
2 : of or relating to a vibration on a celestial body (as the moon) comparable to a seismic event on earth
3 : having a strong or widespread impact : earthshaking <seismic social changes>

— seis·mi·cal·ly \-mi-k(ə-)lē\ adverb