Type of murderer (6,6)
I believe the answer is:
serial killer
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">type of murderer</span>' is the definition.<br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for serial killer that I've seen before include "Regular butcher" , "One carrying out a run of murders" , "Mass murderer" , "One perpetrating many murders at different times" .)