Fighting lawsuit (6)
I believe the answer is:
action
I believe this clue is a double definition.
'fighting' is the first definition.
(action can mean action in war)
'lawsuit' is the second definition.
(synonyms)
(Other definitions for action that I've seen before include "instruction from director" , "Battle or lawsuit, maybe" , "Lawsuit; something done" , "A judicial proceeding brought by one party against another" , "Deed - lawsuit - battle" .)