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

Some are clearly seismic, like bereavement, illness or war. —Mark Travers, Forbes.com, 6 Sep. 2025

Researchers performed over 100 numerical simulations of the continental collision, comparing their models to real-world seismic and geochemical data. —Mrigakshi Dixit, Interesting Engineering, 4 Sep. 2025

The researchers' findings were based on seismic readings from NASA’s InSight lander on Mars. —Eric Lagatta, USA Today, 4 Sep. 2025

Matter of fact, an outright upset would be less than a seismic shock. —Miami Herald, 3 Sep. 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)