seismic

adjective

seis·​mic ˈsīz-mik 

ˈsīs-

1

: of, subject to, or caused by an earthquake

also : of or relating to an earth vibration caused by something else (such as an explosion or the impact of a meteorite)

2

: of or relating to a vibration on a celestial body (such as the moon) comparable to a seismic event on earth

3

: having a strong or widespread impact : earthshaking

seismic social changes

seismically

ˈsīz-mi-k(ə-)lē 

adverb

Examples of seismic in a Sentence

Seismic social changes have occurred.

Recent Examples on the Web

With aftershocks and recurrent seismic activity likely, the region faces ongoing risk. —Hollie Silverman, MSNBC Newsweek, 14 Oct. 2025

In the 10 years since GM developed its strategy to develop a full portfolio of EVs, seismic issues repeatedly roiled the industry and put strain on the company’s capital. —Jackie Charniga, USA Today, 13 Oct. 2025

In the 10 years since GM developed its strategy to develop a full portfolio of EVs, seismic issues repeatedly roiled the industry and put strain on the company’s capital. —Jackie Charniga, Freep.com, 10 Oct. 2025

Many of these landslides are caused by earthquakes, making turbidite layers a useful proxy for pinpointing past seismic events. —Jack Tamisiea, Scientific American, 10 Oct. 2025

Word History

Etymology

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

First Known Use

1858, in the meaning defined at sense 1

Phrases Containing seismic

• seismic shift

Kids Definition

seismic

adjective

seis·​mic ˈsīz-mik 

ˈsīs-

: of, subject to, or caused by an earthquake or an earth vibration caused by something else (as an explosion)