B1[U]a mistake, especially something for which you are to blame: It's not my fault she didn't come!She believes it was the doctor's fault that Peter died.The fault was/lay with the organizers, who failed to make the necessary arrangements for dealing with so many people.Through no fault of his own, he spent a week locked up in jail.Faults and mistakesB2[C]a weakness in a person's character: He has many faults, but dishonesty isn't one of them.Faults and mistakesB2[C]a broken part or weakness in a machine or system: The car has a serious design fault.I think it's got an electrical fault.For all its faults, our transport system is still better than that in many other countries.Faults and mistakes›[C](in tennis and some other games) a mistake made by a player who is beginning a game by hitting the ballTennis and racket sportsFaults and mistakesbe at faultB2to have done something wrong: Her doctor was at fault for/in not sending her straight to a specialist.Making mistakesfind fault with sb/sthC2to criticize someone or something, especially without good reasons: He's always finding fault with my work.Disapproving and criticizingDamaging reputation