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

According to seismic officials, the offshore quake did not trigger a new tsunami alert, and there were no immediate reports of serious damage or injuries as monitoring agencies assessed the impact. —Gabe Whisnant, MSNBC Newsweek, 10 Dec. 2025

That means a lot of subsurface work, such as seismic surveys, stratigraphic mapping and reservoir characterization – potentially taking years – would need to be done before any drilling would begin. —Skip York, The Conversation, 9 Dec. 2025

In addition to the release of Quantum Leap, which is due to arrive in 2026, Wyclef is currently prepping to celebrate a series of seismic moments this coming year. —Preezy Brown, VIBE.com, 9 Dec. 2025

However, the seismic fluctuations of the country’s trade relationships have cost farmers major profits. —Kate Nishimura, Sourcing Journal, 9 Dec. 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)