To fire (5)
I believe the answer is:
shoot
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">to fire</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that shoot is a more specific form of the action discharge)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for shoot that I've seen before include "Fire (a gun)" , "Make a film" , "Kill; part of plant" , "New growth; last word of Hamlet" , "Film; move rapidly" .)