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

The sunny scene must now feel an age ago since Infantino caused a seismic rift in global soccer. — Graham Dunbar, Fortune, 2 Aug. 2026

Going back further, the two most seismic trade deadlines under the current ownership group came in 2004 and 2008. — Mac Cerullo, Boston Herald, 2 Aug. 2026

As offshore wind expands globally, finding cost-effective ways to harden infrastructure in seismic zones is vital. — Mrigakshi Dixit, Interesting Engineering, 31 July 2026

Salt Lake City sits along the Wasatch Fault zone, making the unreinforced masonry of the temple highly vulnerable to seismic activity. — William Jones, USA Today, 30 July 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)