ˈbæd.li ˈɡɹeɪvli ɪl ˈsɪəɹi.əsli ˈsɪɹi.əsli (‘ill’ is often used as a combining form) in a poor or improper or unsatisfactory manner; not well he was ill prepared it ill befits a man to betray old friends the car runs badly he performed badly on the exam the team played poorly ill-fitting clothes an ill-conceived plan with unusual distress or resentment or regret or emotional display they took their defeat badly took her father's death badly conducted himself very badly at the time of the earthquake unfavorably or with disapproval tried not to speak ill of the dead thought badly of him for his lack of concern in a disadvantageous way; to someone's disadvantage the venture turned out badly for the investors angry that the case was settled disadvantageously for them without skill or in a displeasing manner she writes badly I think he paints very badly to a severe or serious degree fingers so badly frozen they had to be amputated badly injured a severely impaired heart is gravely ill was seriously ill very much; strongly I wanted it badly enough to work hard for it the cables had sagged badly they were badly in need of help he wants a bicycle so bad he can taste it with great intensity (‘bad’ is a nonstandard variant for ‘badly’) the injury hurt badly the buildings were badly shaken it hurts bad we need water bad in a disobedient or naughty way he behaved badly in school he mischievously looked for a chance to embarrass his sister behaved naughtily when they had guests and was sent to his room evilly or wickedly treated his parents badly to steal is to act badly