seismic

adjective

seis·​mic ˈsīz-mik How to pronounce seismic (audio)
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 How to pronounce seismic (audio)
adverb

Examples of seismic in a Sentence

Seismic social changes have occurred.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The agency is closely monitoring seismic activity to assess whether more eruptions are likely in the coming days. — Gordon G. Chang, MSNBC Newsweek, 8 Apr. 2025 The woolly mouse, to a minor extent, and the dire wolves, to a scientifically seismic one, are first steps in that direction. — Jeffrey Kluger, Time, 7 Apr. 2025 The shift from Mary Mary to solo artist was seismic, but Erica took it in stride. — Shelby Stewart, Essence, 2 Apr. 2025 Though the plant’s physical address is in what has traditionally been rural Bryan County, the seismic impact of its $7.59 billion investment is rippling out across neighboring counties and spreading across the entire state. — Jim Zahner, USA Today, 1 Apr. 2025 See All Example Sentences for seismic

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

Time Traveler
The first known use of seismic was in 1858

Phrases Containing seismic

Browse Nearby Words

seismetic
seismic
seismicity
See all Nearby Words

Cite this Entry

“Seismic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/seismic. Accessed 13 Apr. 2025.

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Kids Definition

seismic

adjective
seis·​mic ˈsīz-mik How to pronounce seismic (audio)
ˈsīs-
: of, subject to, or caused by an earthquake or an earth vibration caused by something else (as an explosion)

More from Merriam-Webster on seismic

Nglish: Translation of seismic for Spanish Speakers

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