Den denizen (4)
I believe the answer is:
bear
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">den denizen</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for bear that I've seen before include "Carry; large mammal" , "Situation where there are more sellers than willing buyers" , "Hack" , "Tolerate; animal" , "Relating to charged particles" .)