Definition from Wiktionary, the free dictionary
- In a bad manner.
- Very much; to a great degree.
- I want it so badly.
Usage notes 
- Badly is sometimes used after feel in its copulative sense where one might expect an adjective, ie, bad. Most prescriptive grammarians prefer "I feel bad" to "I feel badly", but "I feel badly" is widely used.
in a bad manner