[ fawlt ]
See synonyms for fault on Thesaurus.com
  1. a defect or imperfection; flaw; failing: a fault in the brakes;a fault in one's character.

  2. responsibility for failure or a wrongful act: It is my fault that we have not finished.

  1. an error or mistake: a fault in addition.

  2. a misdeed or transgression: to confess one's faults.

  3. Sports. (in tennis, handball, etc.)

    • a ball that when served does not land in the proper section of an opponent's court.

    • a failure to serve the ball according to the rules, as from within a certain area.

  4. Geology, Mining. a break in the continuity of a body of rock or of a vein, with dislocation along the plane of the fracture (fault plane ).

  5. Manège. (of a horse jumping in a show) any of a number of improper executions in negotiating a jump, as a tick, knockdown, refusal, or run-out.

  6. Electricity. a partial or total local failure in the insulation or continuity of a conductor or in the functioning of an electric system.

  7. Hunting. a break in the line of scent; a losing of the scent; check.

  8. Obsolete. lack; want.

verb (used without object)
  1. to commit a fault; blunder; err.

  2. Geology. to undergo faulting.

verb (used with object)
  1. Geology. to cause a fault in.

  2. to find fault with, blame, or censure.

Idioms about fault

  1. at fault,

    • open to censure; blameworthy: to be at fault for a mistake.

    • in a dilemma; puzzled: to be at fault as to where to go.

    • (of hounds) unable to find the scent.

  2. find fault, to seek and make known defects or flaws; complain; criticize: He constantly found fault with my behavior.

  1. to a fault, to an extreme degree; excessively: She was generous to a fault.

Origin of fault

First recorded in 1250–1300; Middle English faute, faulte, from Anglo-French, Middle French, from unattested Vulgar Latin fallita, noun use of feminine of unattested fallitus, for Latin falsus, past participle of fallere “to be wrong”

synonym study For fault

1. Fault, failing, foible, weakness, vice imply shortcomings or imperfections in a person. Fault is the common word used to refer to any of the average shortcomings of a person; when it is used, condemnation is not necessarily implied: A quick temper is her greatest fault. Foible, failing, weakness all tend to excuse the person referred to. Of these foible is the mildest, suggesting a weak point that is slight and often amusing, manifesting itself in eccentricity rather than in wrongdoing: the foibles of artists. Weakness suggests that the person in question is unable to control a particular impulse, and gives way to self-indulgence: a weakness for pretty women. Failing is closely akin to fault, except that it is particularly applied to humanity at large, suggesting common, often venial, shortcomings: Procrastination and making excuses are common failings. Vice (which may also apply to a sin in itself, apart from a person: the vice of gambling ) is the strongest term, and designates a habit that is truly detrimental or evil.

Other words for fault

Opposites for fault

Other words from fault

  • post·fault, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use fault in a sentence

British Dictionary definitions for fault


/ (fɔːlt) /

  1. an imperfection; failing or defect; flaw

  2. a mistake or error

  1. an offence; misdeed

  2. responsibility for a mistake or misdeed; culpability

  3. electronics a defect in a circuit, component, or line, such as a short circuit

  4. geology a fracture in the earth's crust resulting in the relative displacement and loss of continuity of the rocks on either side of it

  5. tennis squash badminton an invalid serve, such as one that lands outside a prescribed area

  6. (in showjumping) a penalty mark given for failing to clear or refusing a fence, exceeding a time limit, etc

  7. hunting an instance of the hounds losing the scent

  8. deficiency; lack; want

  9. at fault

    • guilty of error; culpable

    • perplexed

    • (of hounds) having temporarily lost the scent

  10. find fault to seek out minor imperfections or errors (in); carp (at)

  11. to a fault excessively

  1. geology to undergo or cause to undergo a fault

  2. (tr) to find a fault in, criticize, or blame

  1. (intr) to commit a fault

Origin of fault

C13: from Old French faute, from Vulgar Latin fallita (unattested), ultimately from Latin fallere to fail

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for fault


[ fôlt ]

  1. A fracture in a rock formation along which there has been movement of the blocks of rock on either side of the plane of fracture. Faults are caused by plate-tectonic forces. See more at normal fault reverse fault strike-slip fault thrust fault transform fault. See Note at earthquake.

a closer look

Bedrock, the solid rock just below the soil, is often cracked along surfaces known as planes. Cracks can extend up to hundreds of kilometers in length. When tensional and compressional stresses cause rocks separated by a crack to move past each other, the crack is known as a fault. Faults can be horizontal, vertical, or oblique. The movement can occur in the sudden jerks known as earthquakes. Normal faults, or tensional faults, occur when the rocks above the fault plane move down relative to the rocks below it, pulling the rocks apart. Where there is compression and folding, such as in mountainous regions, the rocks above the plane move upward relative to the rocks below the plane; these are called reverse faults. Strike-slip faults occur when shearing stress causes rocks on either side of the crack to slide parallel to the fault plane between them. Transform faults are strike-slip faults in which the crack is part of a boundary between two tectonic plates. A well-known example is the San Andreas Fault in California. Geologists use sightings of displaced outcroppings to infer the presence of faults, and they study faults to learn the history of the forces that have acted on rocks.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for fault


In geology, a place where sections of the crust of the Earth move relative to each other. (See earthquake and San Andreas fault.)

Notes for fault

Faults tend to occur near the edges of tectonic plates.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Other Idioms and Phrases with fault


see at fault; find fault; to a fault.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.