Paid fighter (9)
I believe the answer is:
mercenary
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">paid fighter</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for mercenary that I've seen before include "Bent on making money" , "Professional soldier serving in a foreign army" , "One who fights for foreign country for pay" , "Paid soldier" , "Acting for money" .)