Perfects (5)
I believe the answer is:
hones
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">perfects</span>' is the definition.<br/ ><span class="explanation-format__explanation">('hone' can be a synonym of 'perfect')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for hones that I've seen before include "Sharpens on strap, say razor" , "Perfects, sharpens" , "Sharpens as on whetstone" , "Sharpens, like knife on stone" , "gets sharp" .)