In a bad way (6)
I believe the answer is:
evilly
'in a bad way' is the definition.
(I've seen this in another clue)
'bad way' is the wordplay.
'bad' becomes 'evil' (associated in meaning).
'way' becomes 'ly' (I can't justify this - if you can you should believe this answer much more).
'evil'+'ly'='EVILLY'
Can you help me to learn more?
(Other definitions for evilly that I've seen before include "With wicked intent" , "Extremely wickedly" , "in a bad way" , "In wicked or depraved way" , "In a very wicked manner" .)