ERROR

[noun] - a mistakeHe admitted that he'd made an error. [C]The letter contains a number of typing errors, which I must correct. [C]Human error has been blamed for the air crash. [U]I'm sorry - I took your umbrella in error (= by mistake). [U]With something as delicate as brain surgery, there is little margin for error (= you must not make mistakes). [U](formal or humorous) He was always trying to borrow money, but now he sees the error of his ways (= understands that his behaviour was wrong).An error of judgment is a wrong decision.Not telling the staff before they read the bad news in the papers was an error of judgment.