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

In the right hands, blankness can become boldness—without extra permits for plumbing or a million dollars of seismic steel. —Spencer Elliott, Forbes.com, 13 May 2025

By Henry Gass Staff writer The U.S. Supreme Court will hear arguments this week in a case that is both unusual and potentially seismic in its consequences. —Sarah Matusek, Christian Science Monitor, 13 May 2025

This entire rotation was here for last year’s seismic semifinal run. —Steven Louis Goldstein, New York Times, 13 May 2025

Scientists have found seismic clues that suggest liquid water may be hiding beneath Mars' surface. —Victoria Corless, Space.com, 12 May 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)