General English

  • noun the fact of making a mistake or of being to blame for something going wrong
  • noun an instance of something not working properly

General Science

  • noun a feature that spoils the overall quality of something
  • noun a change in the position of the rock layers of the Earth’s crust in response to stress, leading to earthquakes


  • noun a defect in a circuit or wiring caused by bad connections, etc.

Cars & Driving

  • noun a defect which is either inherent in the vehicle as built (manufacturing fault) or which occurs during running


  • noun an act of not working properly


  • noun a situation in which something has gone wrong with software or hardware, causing it to malfunction


  • A defect in an electrical system caused by poor insulation, imperfect connections, grounding, or shorting.
  • A shifting along a plane in a rock formation that causes differential displacement.


  • A defect in a component, circuit, device, piece of equipment, or system, which impairs operation significantly or that causes a failure. Also, a failure caused by such a defect.
  • In a component or circuit, a defect such as a short circuit, an open circuit, or an unintentional ground. Also, a failure caused by such a defect. Also called electrical fault.
  • A defective region in a component, circuit, or device.
  • An error or defect in computer software or hardware. Said especially of one which causes a failure. When such a fault is persistent, also called bug (1).


  • a flaw in a wine that causes it to be atypical of the style of wine and impairs enjoyment

Origin & History of “fault”

like fail, fallacy, fallible, and false, fault comes ultimately from Latin fallere ‘deceive, fail’. Its past participle formed the basis of a vulgar Latin noun *fallita ‘failing, falling short’, which passed into English via Old French faute in the sense ‘lack, deficiency’. The notion of ‘moral culpability’ does not seem to have become incorporated into the word until the late 14th century.