seis·​mic | \ ˈsīz-mik How to pronounce seismic (audio) , ˈsīs-\

Definition of seismic

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

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Other Words from seismic

seismically \ ˈsīz-​mi-​k(ə-​)lē How to pronounce seismically (audio) \ adverb

Examples of seismic in a Sentence

Seismic social changes have occurred.

Recent Examples on the Web

In a point-and-click world, that was a seismic move. TRC Lab is selling like hotcakes. Martha Mccully, Los Angeles Times, "Browsing: Shopping for rugs with interior designer Adam Hunter," 17 Sep. 2019 Deforestation and the use of highly destructive explosives mean these areas are prone to increased seismic tremors and landslides. Gayathri D Naik, Quartz India, "India, leave those forests on the mountains alone, lest you want to drown," 13 Sep. 2019 While this has happened multiple times during human history, there have been only three seismic communications revolutions. Mike Martin, Time, "How the Long History of Human Violence Explains Why the Internet Causes So Much Chaos," 11 Sep. 2019 Businesses rethinking social purpose Business is waking up to these seismic shifts. Bruce Deboskey, The Denver Post, "On Philanthropy: In the eyes of business leaders, “social purpose” has replaced “shareholder capitalism”," 8 Sep. 2019 These are films that are seismic in their reach and leave those who missed out on seeing them in a pop culture blindspot. Richard Newby, The Hollywood Reporter, "'It: Chapter Two' and the Weight of Expectations," 7 Sep. 2019 Our potential upsets for 2019 aren’t that seismic — who could have begun to see those coming? Los Angeles Times, "College football 2019: Which games could provide this year’s major upset?," 23 Aug. 2019 But her election itself was seismic and may yet prove part of a broader shift. Neil Shea, National Geographic, "Tokyo became a megacity by reinventing itself," 12 June 2019 The crowds were sizable and committed — organizers claimed 100,000 walked down Pall Mall — but the demonstrations were not seismic. William Booth, Washington Post, "‘The decision of a lifetime’: Protesters in London call for another Brexit vote," 23 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'seismic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of seismic

1858, in the meaning defined at sense 1

History and Etymology for seismic

Greek seismos shock, earthquake, from seiein to shake; probably akin to Avestan thwaēshō fear

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Statistics for seismic

Last Updated

11 Oct 2019

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Time Traveler for seismic

The first known use of seismic was in 1858

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More Definitions for seismic



English Language Learners Definition of seismic

technical : of, relating to, or caused by an earthquake
: very great or important

More from Merriam-Webster on seismic

Spanish Central: Translation of seismic

Nglish: Translation of seismic for Spanish Speakers

Comments on seismic

What made you want to look up seismic? Please tell us where you read or heard it (including the quote, if possible).


fear of the number 13

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