Definition of "earthquake"

Her alablaster brest she soft did kis, / Which all that while shee felt to pant and quake, / As it an Earth-quake were: at last she thus bespake.

1590, Edmund Spenser, “Book III, Canto II”, in The Faerie Queene. […], London: […] [John Wolfe] for William Ponsonbie

Last year's earthquake crushed his house, his livelihood and very nearly his leg, he said, pointing to a plastered limb that refuses to heal.

2006 October 6, Declan Walsh, The Guardian

Since the response of some man-made structures to the ground motion near the epicenter is highly dependent on frequency, a significant difference in potential damage to the structures is expected between earthquakes and moonquakes.

1988, Jürgen Oberst, Yosio Nakamura, “A seismic risk for the lunar base”, in The Second Conference on Lunar Bases and Space Activities of the 21st Century, volume 1, NASA, pages 231–233

The wave patterns, too, are strikingly different: The secondary (S) waves and surface waves on lunar seismograms are not generally as clearly defined and distinct as are those of earthquakes.

2006, Bruce A. Bolt, Earthquakes, Fifth Edition

As we have seen, economic earthquakes often result in political shockwaves. […] He highlights a correlation between those states with the highest robot density and those states that unexpectedly swung behind Donald Trump in the 2016 presidential election, namely Michigan, Pennsylvania and Wisconsin.

2019 July 11, John Thornhill, “Does tech threaten to rerun the worst of the Industrial Revolution?”, in Financial Times‎

Watch the Philippines very closely for the next little while. There is rumbling and earthquaking deep within Pinatubo and increased earthquaking within Mayon.

1993, Gyeorgos C. Hatonn, The Best of Times: The Worst of Times, page 129