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 According to Boston 25 News meteorologist Vicki Graf, earthquakes on the East Coast are felt over a larger area due to seismic waves traveling farther and older rock formations. Fox News, "Earthquake in Massachusetts rattles New England, triggers reaction online," 8 Nov. 2020 In the late 1970s, the country was fighting its way out of recession and a period of economic stagnation that had contributed to a national malaise and led to seismic change in the 1980 presidential election. Vance Stuehrenberg, Star Tribune, "Forty years of the Staggers Rail Act," 13 Oct. 2020 Kohler says that when seismic waves from an earthquake enter the softer sediments that fill in the basin underneath Los Angeles, the waves slow down and their energy piles up, creating larger amplitude waves that lead to stronger shaking. Eric Niiler, Wired, "The Most Sway-Prone Buildings in LA Aren’t Where You Expect," 9 Oct. 2020 Tom Karlo, who started working at San Diego’s public-broadcasting station, KPBS, as a college student in 1973 and rose through the ranks to become general manager during a period of seismic change in the media world, announced his retirement Monday. John Wilkens, San Diego Union-Tribune, "KPBS GM Karlo says he will retire at year’s end," 5 Oct. 2020 There are actually several types of seismic waves released by earthquakes, and each behaves a bit differently. Scott K. Johnson, Ars Technica, "Seismic sound waves crossing the deep ocean could be a new thermometer," 26 Sep. 2020 These sounds are not the seismic waves from the quakes, which travel through the earth’s crust. Stephanie Pappas, Scientific American, "Earthquake Sounds Could Reveal How Quickly the Ocean Is Warming," 17 Sep. 2020 And there will be a seismic change on the field amid the movement for racial equality and social justice. Janet Shamlian, CBS News, "NFL in uncharted territory as new season kicks off amid pandemic," 10 Sep. 2020 Lamont-Doherty's 40-second plot of the same data (Graph 2) gives a much more detailed picture: The seismic waves—blue for the South Tower, red for the North Tower—start small and then escalate as the buildings rumble to the ground. Popular Mechanics Editors, Popular Mechanics, "Debunking the 9/11 Myths: Special Report - The World Trade Center," 9 Sep. 2020

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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Time Traveler for seismic

Time Traveler

The first known use of seismic was in 1858

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Statistics for seismic

Last Updated

19 Nov 2020

Cite this Entry

“Seismic.” Dictionary, Merriam-Webster, Accessed 23 Nov. 2020.

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More Definitions for seismic


How to pronounce seismic (audio)

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

Nglish: Translation of seismic for Spanish Speakers

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