Resoluteness (13)
I believe the answer is:
determination
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">resoluteness</span>' is the definition.<br/ ><span class="explanation-format__explanation">(determination is a kind of resoluteness)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for determination that I've seen before include "Willpower" , "Firm resolve" , "Resolution" , "Firmness of purpose" , "24 [DRIVE]" .)