Dent (5)
I believe the answer is:
notch
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dent</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for notch that I've seen before include "Snick" , "Dent" , "Nick - incision" , "V-shaped incision" , "V-shaped nick" .)