1in an unsatisfactory, inadequate, or unsuccessful way:England have played badly this year the war was going badly in a critical or unfavourable way:try not to think badly of me in an unacceptable or unpleasant way:she realized she was behaving rather badly
2used to emphasize the seriousness of an unpleasant event or action:the building was badly damaged by fire very much or intensely:I wanted a baby so badly
3in a guilty or regretful way:I felt badly about my unfriendliness