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 2001, a cluster of seismic activity culminated in a magnitude 2.9 earthquake., "Swarm of small earthquakes shakes slopes of Mount Hood," 9 July 2019 California's governor is calling the seismic activity a wake-up call. CBS News, "Some California residents so rattled by big earthquakes they're sleeping outside," 8 July 2019 Since 2006, the United States Geological Survey has been developing a network of sensors up and down the West Coast to detect potentially damaging seismic activity. New York Times, "Californians’ Alert Apps Didn’t Sound for 2 Big Earthquakes. Why Not?," 8 July 2019 The seismic activity is unlikely to affect fault lines outside of the area, Jones said, noting that the gigantic San Andreas Fault is far away. John Antczak, Time, "California Governor: Earthquakes Are a 'Wake-Up Call'," 7 July 2019 Filling out the subsurface picture Analysis of the seismic data is an enormous task. Emilie Hooft, The Conversation, "We probed Santorini’s volcano with sound to learn what’s going on beneath the surface," 24 June 2019 This estimate comes from a new study, published today in Science, that dug through seismic data between 2008 and 2017 and found that Southern California experienced a startling 1.81 million temblors during that decade. Maya Wei-haas, National Geographic, "Every three minutes, an earthquake strikes in California," 18 Apr. 2019 But even a partial adherence to it could be seismic. Matt Ford, The New Republic, "Clarence Thomas’s Unprecedented America," 26 June 2019 While the big story of the 2018 election was the Blue Wave that swept Democrats into the House majority, the rise of the party’s progressive wing also has had a seismic impact. San Diego Union-Tribune, "Column: Green New Deal popularity among Democrats alters San Diego’s political landscape," 21 June 2019

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

19 Jul 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).


appealing forcibly to the mind or reason

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