Will-power (8)
I believe the answer is:
volition
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">will</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that will can be written as volition)</span><br/ ><br/ >'<span class="explanation-format__original">power</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(volition is a kind of power)</span><br/ ><br/ ></span>
(Other definitions for volition that I've seen before include "Act of exercising the will" , "Power of using one's will" , "The act of makiing a choice" , "Free will" , "(Exercise of) will" .)