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

Keep scrolling for more

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

Miners said upstream dams shouldn’t automatically be considered unsafe because of the recent accident in Brumadinho and that environmental considerations have to be taken into account, including seismic activity and climate. Rhiannon Hoyle, WSJ, "Vale Denied Having ‘Upstream’ Dams Ahead of Deadly Accident," 10 Feb. 2019 While Puerto Rico has building codes in place that help structures withstand hurricanes and seismic activity—even older buildings built to past codes survived with minimal damage—informal housing isn’t constructed to this criteria. Diana Budds, Curbed, "How architects and designers are rebuilding Puerto Rico," 20 Sep. 2018 The seismic activity Sunday would not be a roadblock to petroleum development, West said. Dan Joling, The Seattle Times, "Alaska’s North Slope shaken by 2 largest recorded quakes," 14 Aug. 2018 The seismometer, known as SEIS, will be examining the planet's internal activity, trying to detect pulses from seismic waves, meteor impacts, and even marsquakes. David Grossman, Popular Mechanics, "InSight Lander Sending Back First Mars Photos," 7 Dec. 2018 The seismic waves from these wobbles will help planetary scientists decode the structure of Mars’ interior, similar to how ultrasounds show us what’s inside a person’s body. Loren Grush, The Verge, "Hanging out at NASA’s Jet Propulsion Laboratory," 27 Nov. 2018 Instead, Dreamcatcher is sending seismic waves through the K-pop world by seamlessly combining polished elements of a girl group with metal ones. Devon Abelman, Allure, "Dreamcatcher Is the Goth-Inspired Girl Group Shaking Up the K-Pop World," 11 Sep. 2018 When sections of the Earth’s crust slip beneath or past one another, energy is released in the form of seismic waves. Annie Roth, National Geographic, "No, World Cup Fans Didn't Trigger an Earthquake. Here's Why.," 18 June 2018 Because seismic waves move through different materials at different speeds and angles, scientists can use marsquake data to figure out the structure and composition of the interior of the planet. Eva Botkin-kowacki, The Christian Science Monitor, "How NASA's latest mission to Mars might dig up truths about Earth," 7 May 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.

See More

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

Keep scrolling for more

Learn More about seismic

Statistics for seismic

Last Updated

15 Feb 2019

Look-up Popularity

Time Traveler for seismic

The first known use of seismic was in 1858

See more words from the same year

Keep scrolling for more

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).


very full or close together

Get Word of the Day daily email!

Test Your Vocabulary

What did you just call me?! A Quiz

  • rows-of-various-emoji
  • If a member of the audience describes your speech as bombastic, does that person mean it is:
True or False

Test your knowledge - and maybe learn something along the way.


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!