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

Kim is a co-author of the study, published 17 September in Science, which details Mount Mantap’s ongoing seismic activity. — Tom Metcalfe, Scientific American, 17 Sep. 2026

However, according to seismic wave data from 2008 to 2025 collected and analyzed by Kim in South Korea and his colleagues in China, the area around Mount Mantap experienced 1,399 earthquakes, with the number and magnitude increasing over time. — Katie Hunt, CNN Money, 17 Sep. 2026

This walk-off rescued the Guardians from a deflating defeat that would have delivered a seismic blow to their AL Central chances. — Zack Meisel, New York Times, 16 Sep. 2026

That was like the youth club dream and felt as seismic as things would ever be. — Thomas Smith, Billboard, 16 Sep. 2026

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)