n. 1
A defect, imperfection, or weakness; more severe than a flaw. A failing of character; less severe than a vice.
Despite all her faults, she’s a good person at heart.
n. 2
Culpability; the responsibility for a blameworthy event.
No, don't blame yourself. It's my fault that we lost the game.
n. 3
A defect, imperfection, or weakness; more severe than a flaw. A characteristic, positive or negative or both, which increases one's risk of danger or difficulty.
You're still young, that's your fault.
v. 1
To criticize, blame or find fault with something or someone.

Related words

Word family: faultfinder fault-finding faultful faultless fault-prone faulty faulter
Phrases: find fault to a fault segmentation fault reverse fault thrust fault

Forms

Plural: faults → errors, mistakes, wrongs, slips…
Past participle: faulted
e.g. faulted → blamed, criticized, accused, censured…

Choose the right word

Fault or Defect?

A defect is the want or lack of something; fault, primarily a failing, is something that fails of an apparent intent or disappoints a natural expectation; thus a sudden dislocation or displacement of geological strata is called a fault.

J. C. Fernald, English Synonyms and Antonyms (1914)

Example sentences

mistake If that man makes one more mistake, I'll fire him.
error He looked over the text, but overlooked the error.
blunder Don't worry about your blunder: it wasn't serious.
defect There must be a defect in the experimental method.
flaw I have one big flaw: finding flaws in others.

Popularity over time

Word	1850 → 2019	Trend
fault		steady
mistake		rising
error		steady
blunder		steady
misdeed		rising
defect		steady

Use in printed books, per decade from 1850 to 2019.

By length

3 letters: sin¹
4 letters: trip¹, vice¹, slip¹, flaw¹, goof¹
5 letters: wrong¹, break¹, shift¹, blame¹, error², lapse¹, fluff¹, taint¹, gaffe¹
6 letters: defect², accuse², foible²
7 letters: mistake², failure², offense², failing², default², offence, stumble², blunder², blemish², censure², frailty², demerit³, misdeed²
8 letters: weakness², fracture², omission³, drawback², trespass², admonish³
9 letters: criticize³, criticise, infirmity⁴
10 letters: deficiency⁴, inaccuracy⁵
11 letters: delinquency⁴, shortcoming³, dereliction⁴
12 letters: imperfection⁴, indiscretion⁴
13 letters: vulnerability⁶, transgression³

The small number after each word is its number of syllables (error² = 2 syllables).

In other languages

Français: faille
Italiano: faglia
Español: falla
Deutsch: Verwerfung