Terminate prematurely (5)
I believe the answer is:
abort
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">terminate prematurely</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for abort that I've seen before include "Pull the plug on" , "Call off (mission) because of problem" , "[FINISH] prematurely" , "Bring to premature conclusion" , "Stop prematurely" .)