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

Traffic, construction projects, mining operations, industrial work, concerts and sporting events all generate small but measurable ground movements known as anthropogenic seismic noise. — Jamie Carter, Forbes.com, 10 Aug. 2026

This area is where the Nazca, South American and Caribbean tectonic plates interact, causing frequent seismic activity. — Mary Randolph, Scientific American, 10 Aug. 2026

Exactly one month after Jaylen Brown’s seismic trade to the Philadelphia 76ers, the former Celtics star addressed the media for the first time. — Zack Cox, Boston Herald, 6 Aug. 2026

There’s little sense of forward motion in these tracks, but even when simply drifting in place, the blend of atmosphere and physicality—sunset glow meets seismic throb—is payoff enough. — Philip Sherburne, Pitchfork, 4 Aug. 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)