Slender candle (5)
I believe the answer is:
taper
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">slender candle</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for taper that I've seen before include "Narrow gradually as candle may" , "See the light" , "Get to the point" , "Get thinner towards the end" , "Thin wick" .)