[adjective] - relating to or caused by an earthquake, or (figurative) having very great and damaging effectsGeological studies show that the area has been free of seismic activity for a long time.(figurative) The news that the chairman would resign set off seismic waves in the business community.(figurative) When the story became public, the reactions from parents were of seismic proportions.
SEISMIC
Meaning of SEISMIC in English
Cambridge English vocab. Кембриджский английский словарь. 2012