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Definition: fault 1 from Merriam-Webster's Collegiate(R) Dictionary

(13c) 1 obs : lack 2 a : weakness failing; esp : a moral weakness less serious than a vice b : a physical or intellectual imperfection or impairment :defect c : an error esp. in service in a net or racket game 3 a : misdemeanor b : mistake 4 : responsibility for wrongdoing or failure 〈the accident was the driver's ⁓〉 5 : a fracture in the crust of a planet (as the earth) or moon accompanied by a displacement of one side of the fracture with respect to the other usu. in a direction parallel to the fracture — at fault 1 : unable to find the scent and continue chase 2 : open to blame :responsible 〈you were really at fault〉 — to a fault : to an excessive degree 〈precise to a fault

syn fault failing frailty foible vice mean an imperfection or weakness of character. fault implies a failure, not necessarily culpable, to reach some standard of perfection in disposition, action, or habit 〈a writer of many virtues and few faults〉. failing suggests a minor shortcoming in character 〈being late is a failing of mine〉. frailty implies a general or chronic proneness to yield to temptation 〈human frailties〉. foible applies to a harmless or endearing weakness or idiosyncrasy 〈an eccentric's charming foibles〉. vice can be a general term for any imperfection or weakness, but it often suggests violation of a moral code or the giving of offense to the moral sensibilities of others 〈compulsive gambling was his vice〉.


Summary Article: fault
from The Columbia Encyclopedia

in geology, fracture in the earth's crust in which the rock on one side of the fracture has measurable movement in relation to the rock on the other side. Faults on other planets and satellites of the solar system also have been recognized. Evidence of faults are found either at the surface (fault surface) or underground (fault plane). Faults are most evident in outcrops of sedimentary formations where they conspicuously offset previously continuous strata. Movement along a fault plane may be vertical, horizontal, or oblique in direction, or it may consist in the rotation of one or both of the fault blocks, with most movements associated with mountain building and plate tectonics. The two classes of faults include the dip-slip (up and down movement), which is further divided into normal and thrust (reverse) faults; and strike-slip (movement parallel to the fault plane). The San Andreas fault of California is of this type. In dip-slip faults the term “hanging wall” is used for the side that lies vertically above the other, called the “footwall.” A fault in which the hanging wall moves down and the footwall is stationary is called a normal fault. Normal faults are formed by tensional, or pull-apart, forces. A fault in which the hanging wall is the upthrown side is called a thrust fault because the hanging wall appears to have been pushed up over the footwall. Such faults are formed by compressional forces that push rock together and are by far the most common of the dip-slip faults. All types of faults have been recognized on the ocean floor: normal faults occur in the rift valleys associated with mid ocean ridges spreading at slow rates; strike-slip faults appear between the offset portions of mid-ocean ridges; and thrust faults occur at subducting plate boundaries. Active faults, though they may not move for decades, can move many feet in a matter of seconds, producing an earthquake. The largest earthquakes occur along thrust faults. Some faults creep from a half inch to as much as 4 in. (1 to 10 cm) per year. Fault movements are measured using laser and other devices. Faults create interpretation problems for geologists by altering the relations of strata (see stratification), such as making the same rock layer offset in two vertical cross sections of a formation or making layers disappear altogether. Faults are often seen on the surface as topographical features, including offset streams, linear lakes, and fault scarps.

The Columbia Encyclopedia, © Columbia University Press 2018

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