Artillery unit (7)
I believe the answer is:
battery
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">artillery unit</span>' is the definition.<br/ ><span class="explanation-format__explanation">(battery is a kind of artillery unit)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for battery that I've seen before include "criminal offence" , "Infliction of violence" , "Means of storing electric current" , "Power cell" , "Source of stored energy" .)