Opportunist (7)
I believe the answer is:
chancer
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">opportunist</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for chancer that I've seen before include "Unscrupulous sort" , "Informally, one who tries his luck" , "Unscrupulous opportunist" , "opportunistic sort" , "One taking risks" .)