Elephant's tooth (4)
I believe the answer is:
tusk
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">elephant's tooth</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 tusk that I've seen before include "Long protruding tooth" , "Ivory-coloured dentine" , "Elephant's dentine" , "Protruding ivory, of elephant say" , "Elongated tooth" .)