Meaning of “badly” - Learner’s Dictionary

badly

adverb uk us /ˈbædli/ (worse, worst)
SERIOUSLY

A2 very seriously:

UNPLEASANT

B2 in a way that is of low quality or in an unpleasant way:

to behave badly
Some of the animals were very badly treated.
They played badly in the first half.

(Definition of “badly” from the Cambridge Learner’s Dictionary © Cambridge University Press)