Horned pachyderm (5)
I believe the answer is:
rhino
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">horned pachyderm</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 rhino that I've seen before include "Horned ungulate" , "Beastly type that could charge you" , "African/Asian ungulate" , "greens" , "Moola" .)