earthquake

n. trembling of the earth (usually produced by volcanic action or other forces under the earth's crust)

An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes are recorded with a seismometer, also known as a seismograph. The moment magnitude  of an earthquake is conventionally reported, or the related and mostly obsolete Richter magnitude, with magnitude 3 or lower earthquakes being mostly imperceptible and magnitude 7 causing serious damage over large areas. Intensity of shaking is measured on the modified Mercalli scale.
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Noun
1. shaking and vibration at the surface of the earth resulting from underground movement along a fault plane of from volcanic activity
(synonym) quake, temblor, seism
(hypernym) geological phenomenon
(hyponym) shock, seismic disturbance
2. a disturbance that is extremely disruptive; "selling the company caused an earthquake among the employees"
(hypernym) disturbance, disruption, commotion, stir, flutter, hurly burly, to-do, hoo-ha, hoo-hah, kerfuffle

(n.)
A shaking, trembling, or concussion of the earth, due to subterranean causes, often accompanied by a rumbling noise. The wave of shock sometimes traverses half a hemisphere, destroying cities and many thousand lives; -- called also earthdin, earthquave, and earthshock.
  

(a.)
Like, or characteristic of, an earthquake; loud; starling.
  

(IBM) The ultimate real-world shock test for computer hardware. Hackish sources at IBM deny the rumor that the San Francisco Bay Area quake of 1989 was initiated by the company to test quality-assurance procedures at its California plants.
[Jargon File]
(1995-04-22)