fault
Pronunciation: /fɔːlt, fɒlt/
noun
- 1an unattractive or unsatisfactory feature, especially in a piece of work or in a person’s character: my worst fault is impatience
- a break or other defect in an electric circuit or piece of machinery: a fire caused by an electrical fault
- a misguided action or habit: the fault of the keen therapist is to start to intervene during the assessment phase
- (in tennis and similar games) a service of the ball not in accordance with the rules.
- (usually faults) (in showjumping) a penalty point imposed for an error.
verb

Phrases
-
at fault
- 1responsible for an undesirable situation; in the wrong: we recover compensation from the person at fault
-
find fault
- make an adverse criticism or objection, sometimes unfairly: he finds fault with everything I do
-
—— to a fault
- displaying the specified commendable quality to an almost excessive extent: you’re kind and generous to a fault

Origin:
Middle English faut(e) 'lack, failing', from Old French, based on Latin fallere 'deceive'. The -l- was added (in French and English) in the 15th century to conform with the Latin word, but did not become standard in English until the 17th century, remaining silent in pronunciation until well into the 18th