From King Dictionary of Contemporary English unable un‧a‧ble / ʌnˈeɪb əl / ●●● W2 adjective [not before noun ] CAN'T not able to do something → inability unable to do something Lucy was unable to find out what had happened. Unable to sleep, I got up and made myself a drink. Register In everyday English, people usually say that they can't/couldn't do something rather than are/were unable to do something: She couldn't find out what had happened. Examples from the Corpus unable • Older people were much more likely than the young to be unable to describe what they meant by health. • If they don't, one should dismiss the idea of cars unable to get out of the garage as sensational rubbish-mongering. • When the police proved unable to handle them, the militia was called out. • When spot market prices rose, the utilities were unable to increase their rates. • But they were unable to produce perfect castings. • Tommy, unable to read, is none the wiser. • Security of tenure also means that a landlord may be unable to regain his house, if he wishes to. • What happens when a young husband and father is suddenly unable to work because of cancer? unable to do something • They were unable to find any link when other variables like prices and incomes were taken into account. • Ben was unable to get out of bed for four days. • Prevention education has been unable to halt this behavior, or even to make much of a dent in it. • The result has been that customers are often unable to log on to the system. • He seemed unable to meet the coroner's eyes, not daring even to look in his direction. • Tebbit found himself unable to outlaw the closed shop entirely. • Three kids trapped by them and unable to return home. • Of much of this process Coffin was a spectator; he was unable to tear himself away. • Well over eighty years of age, and unable to walk without support, he now rarely leaves his room.