May be charged with assault (7)
I believe the answer is:
battery
'assault' is the definition.
(synonyms)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for battery that I've seen before include "it makes poultry grow faster" , "criminal offence" , "Equipment for war" , "crime" , "Power source; artillery unit" .)