Overcharge, informally (4)
I believe the answer is:
soak
'overcharge informally' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for soak that I've seen before include "Get wet" , "Marinate" , "Douse, drench" , "Saturate" , "Habitual drinker (slang)" .)