Understands (5)
I believe the answer is:
twigs
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">understands</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for twigs that I've seen before include "Understands" , "Slender woody shoots" , "Catches on" , "Small branches" , "Slender (tree) shoots" .)