seis·mic | \ ˈsīz-mik , 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 \ adverb

Examples of seismic in a Sentence

Seismic social changes have occurred.

Recent Examples on the Web

The seismic waves from a nearby earthquake will deform the cable minutely, leaving the returning light slightly out of phase with the light emitted by the laser. The Economist, "Submarine cables could be repurposed as earthquake detectors," 16 June 2018 Just like a seismometer, the faster moving primary seismic wave is seen first, with the slower secondary wave right behind it. Scott K. Johnson, Ars Technica, "Seafloor fiber optic cables can work like seismometers," 15 June 2018 Real Madrid are reportedly preparing a bid worth £150m for Chelsea superstar Eden Hazard as the reigning European champions take their first steps towards replacing Cristiano Ronaldo following his seismic move to Juventus earlier this month., "Real Madrid Set to 'Formalise Interest' in Chelsea Superstar Eden Hazard With £150m Bid," 13 July 2018 The hospital’s largest buildings need extensive work to meet the state’s rigorous seismic safety standards that take effect in 2030. Phil Diehl,, "Parking structure approved for Tri-City Medical Center," 11 July 2018 Now, the city’s socioeconomic complexities and seismic battles over gentrification serve as microcosms for the times, allowing the Oakland-centric films of 2018 to start wider conversations and, possibly, wind up in the Oscar race this fall. Jen Yamato,, "Beyond 'Black Panther': Thanks to a wave of homegrown filmmakers, Oakland is having a Hollywood moment," 7 July 2018 Eni, the Italian firm working on the field, has done only seismic surveys of the area. The Economist, "Egypt is optimistic about new gas discoveries in the Mediterranean," 5 July 2018 What was the point of making a seismic trade that promises a runner-up finish that doesn't get them to the big stage? J. Michael, Indianapolis Star, "Insider: LeBron James' departure to the West opens up field for Pacers, Victor Oladipo," 2 July 2018 The United States wasn’t the only country with seismic swings taking place. Patricia Meschino, Billboard, "As Reggae Celebrates 50 Years, Some of the Genre's Pioneers Look Back on Its Worldwide Ascent," 1 July 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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Phrases Related to seismic

seismic shift

Statistics for seismic

Last Updated

16 Aug 2018

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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

: 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).


occurring twice a year or every two years

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