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

Instead of rigid steel, track sections over the bridge’s expansion joints rest on 43-foot-long steel platforms supported by flexing seismic bearings. — Mrigakshi Dixit, Interesting Engineering, 31 Aug. 2026

Indonesia is an archipelago of more than 280 million people with frequent seismic activity and Sinabung is among more than 120 active volcanoes. — ABC News, 31 Aug. 2026

The temple — one of more than 200 LDS temples operating globally — has been closed since late 2019 for renovations to expand its interior, shore up its foundation and make seismic upgrades. — Brandon Griggs, CNN Money, 28 Aug. 2026

The seismic event known as the Los Angeles riots occurred from April 29 to May 4, 1992. — Alison Foreman, IndieWire, 28 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)