Also found in: Thesaurus, Medical, Financial, Encyclopedia, Wikipedia.
Related to hypocenter: reverse fault, Fault scarp


The surface position directly beneath the center of a nuclear explosion.

hy′po·cen′tral (-sĕn′trəl) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈfoʊ kəs)

n., pl. -cus•es, -ci (-sī, -kī), n.
1. a central point, as of attention or activity.
2. a point at which rays of light, heat, or other radiation meet after being refracted or reflected.
a. the focal point of a lens.
b. the focal length of a lens.
c. the clear and sharply defined condition of an image.
d. the position of a viewed object or the adjustment of an optical device necessary to produce a clear image: out of focus.
4. (of a conic section) a point having the property that the distances from any point on a curve to it and to a fixed line have a constant ratio for all points on the curve.
5. the point of origin of an earthquake.
6. the primary center from which a disease develops or in which it localizes.
7. to bring to a focus or into focus: to focus the lens of a camera.
8. to concentrate: to focus one's thoughts.
9. to become focused.
[1635–45; < Latin: fireplace, hearth]
fo′cus•a•ble, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
Mentioned in ?
References in periodicals archive ?
In present-day Hiroshima, the closest reminder of that hour is the Atomic Bomb Dome monument, a former government office near the hypocenter of the blast, its twisted shell a memento of a force beyond anything man had ever seen.
People who were in the hypocenter of the explosions were killed by the heat and the blast effect of the nuclear bombs.
However, for induced seismicity, (1) illustrates that such an increase in acceleration with a decrease in earthquake magnitude is possible due to the shallow hypocenter.
Furthermore, this profile of permeability is suitable for representing rapid hypocenter migration (see Table 1 in [33]).
But the two earthquakes - with hypocenter depths between 50 and 60 km--did not occur in the contact between the two tectonic plates as is usually expected, but rather within the Cocos plate as it bends downward within the mantle.
A major study of atomic bomb survivors, called the Life Span Study, has found that of the nearly 90,000 people who were within 10 kilometers of the hypocenter of those blasts--thousands of whom received frighteningly high initial doses of radiation and continued exposure for months because of contaminated food, water, and air--the lifetime cancer death toll rose by only 0.3% compared with the cancer mortality among 20,000 non-exposed Japanese who have been followed as a control group.
Sileny, J.: 2009, Resolution of non-double-couple mechanisms: Simulation of hypocenter mislocation and velocity structure mismodelling.
In DEM, if each generated microcrack is considered an individual AE event, the magnitude of the AE event caused by the hypocenter of microcrack inversion is almost the same for each event.