seismic
adjective
seis·mic ˈsīz-mik 
ˈsīs-
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
seismically
ˈsīz-mi-k(ə-)lē
adverb 
Example Sentences
Seismic social changes have occurred.
Recent Examples on the Web Many residents, students and workers across the city left buildings and schools and sought safety on the streets as traffic stopped for the second time within an hour Monday as the seismic alarm system went off again. 
Anthony Harrup, WSJ, 19 Sep. 2022 The past couple years, Huntsville has experienced seismic improvements in music here. Matt Wake | Mwake@al.com, al, 16 Sep. 2022 And as a producer, Sanborn has the skill to sweep people away with seismic beats. Piet Levy, Journal Sentinel, 14 Sep. 2022 The report issued by Lamont-Doherty includes various graphs showing the seismic readings produced by the planes crashing into the two towers as well as the later collapse of both buildings. Popular Mechanics Editors, Popular Mechanics, 9 Sep. 2022 And the ascension of Prince Charles to the British throne promises to have a seismic effect on the roles of other royals orbiting the crown. Marco Della Cava, USA TODAY, 9 Sep. 2022 Oscar slap seen around the world hasn’t addressed the seismic news in a big sit-down interview yet. Duante Beddingfield, Detroit Free Press, 8 Sep. 2022 In what has been a seismic and somber day in the UK, The King has paid tribute to his mother, Her Majesty Queen Elizabeth II in a statement via Buckingham Palace. Roxanne Adamiyatt, Town & Country, 8 Sep. 2022 But in the wake of the film's seismic success, which included a Best Screenplay Oscar for Peele (the first ever won by a Black person in that category), that's beginning to change. Randall Colburn, EW.com, 6 Sep. 2022 See More
Anthony Harrup, WSJ, 19 Sep. 2022 The past couple years, Huntsville has experienced seismic improvements in music here. Matt Wake | Mwake@al.com, al, 16 Sep. 2022 And as a producer, Sanborn has the skill to sweep people away with seismic beats. Piet Levy, Journal Sentinel, 14 Sep. 2022 The report issued by Lamont-Doherty includes various graphs showing the seismic readings produced by the planes crashing into the two towers as well as the later collapse of both buildings. Popular Mechanics Editors, Popular Mechanics, 9 Sep. 2022 And the ascension of Prince Charles to the British throne promises to have a seismic effect on the roles of other royals orbiting the crown. Marco Della Cava, USA TODAY, 9 Sep. 2022 Oscar slap seen around the world hasn’t addressed the seismic news in a big sit-down interview yet. Duante Beddingfield, Detroit Free Press, 8 Sep. 2022 In what has been a seismic and somber day in the UK, The King has paid tribute to his mother, Her Majesty Queen Elizabeth II in a statement via Buckingham Palace. Roxanne Adamiyatt, Town & Country, 8 Sep. 2022 But in the wake of the film's seismic success, which included a Best Screenplay Oscar for Peele (the first ever won by a Black person in that category), that's beginning to change. Randall Colburn, EW.com, 6 Sep. 2022 See More Word History
Etymology
Greek seismos shock, earthquake, from seiein to shake; probably akin to Avestan thwaēshō fear
First Known Use
1858, in the meaning defined at sense 1