Cranefly grub (13)
I believe the answer is:
leatherjacket
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cranefly grub</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 leatherjacket that I've seen before include "Swimmer" , "Cranefly larva" , "Cranefly grub" , "Garden pest - crane fly larva" , "Hold close" .)