Professional killer (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">professional killer</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for gunman that I've seen before include "As killer" , "Eg, sniper" , "Sean O'Casey play 'Shadow of a . . . . . .'" , "Armed criminal" , "Armed person" .)
(Other definitions for hitman that I've seen before include "offer?" , "Hired gun" , "Assassin" , "killer" .)