Run away from line overwhelmed by charge (4)
I believe the answer is:
flee
'run away from' is the definition.
(thesaurus)
'line overwhelmed by charge' is the wordplay.
'line' becomes 'l'.
'overwhelmed by' is an insertion indicator (I've seen this in other clues).
'charge' becomes 'fee' (fee is a kind of charge**).
'l' going within 'fee' is 'FLEE'.
(Other definitions for flee that I've seen before include "head for the hills" , "Cut and run" , "Run quickly away" , "Do a runner" , "Leave" .)