Elephant (5)
I believe the answer is:
jumbo
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">elephant</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 jumbo that I've seen before include "Enormous" , "monster" , "Huge and bulky" , "Elephant - large aircraft" , "Owner of trunk" .)