earthquake

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A sudden movement of the earth's crust caused by the release of stress accumulated along geologic faults or by volcanic activity. Also called seism, temblor.

Century Dictionary and Cyclopedia

1. n. A movement or vibration of a part of the earth's crust. Such movements are of every degree of violence, from those that are scarcely perceptible without the aid of apparatus specially contrived for the purpose to those which overthrow buildings, rend the ground asunder, and destroy thousands of human lives. The duration of earthquakes is as variable as their intensity. Sometimes there is a single shock, lasting only a second or two; at other times a great number of shocks occur in succession, separated by greater or less intervals of time, the earth not being reduced to complete quiescence for weeks or even months. It is not known that any portion of the earth's surface is entirely exempt from earthquakes; but there are large areas where no very destructive ones have ever occurred, either in the memory of man or as recorded in history. The regions most frequently visited by destructive shocks are those where active volcanoes exist, those near high mountain-ranges, and those where the rocks are of recent geological age, and are much disturbed or uplifted. Such regions are the vicinity of the Mediterranean, the shores of the Pacific and the adjacent islands, the neighborhood of the Alps, and the East India islands. Regions not liable to seismic disturbances are the whole of northeastern North America, the east side of South America, the north of Asia, and a large part of Africa. An earthquake-shock is a wave-like motion of a part of the earth's crust, and, in the words of Humboldt, is one of the ways in which the reaction of the interior of the earth against its exterior makes itself manifest. The most destructive earthquake of which we have any knowledge was that of Lisbon. It began November 1st, 1755, and was felt over that part of the earth's surface included between Iceland on the north, Mogador in Morocco on the south, Töplitz in Bohemia on the east, and the West India islands on the west. The destruction of life and property occasioned by this shock was very great. The disturbance continued, especially in the vicinity of the Mediterranean, with short intermissions, for several months. On November 18th, 1755, the most violent shock occurred which has been felt in New England since its settlement by the whites. One of the most destructive earthquakes of recent occurrence was that which took place on the island of Ischia near Naples, July 28th, 1883, by which over 2,000 persons perished. By the earthquake at Mendoza, South America, on the 20th of March, 1861, over 12,000 persons lost their lives. A violent earthquake, most destructive in Charleston, south Carolina, and vicinity, occurred on the night of August 31st, 1886. See seismic, seismometer, and volcanism.

GNU Webster's 1913

1. 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.
2. adj. Like, or characteristic of, an earthquake; loud; startling.

WordNet 3.0

1. n. a disturbance that is extremely disruptive
2. n. shaking and vibration at the surface of the earth resulting from underground movement along a fault plane of from volcanic activity