High rocky hill (3)
I believe the answer is:
tor
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">high rocky hill</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 tor that I've seen before include "Rot about the rocky height" , "Pillar of rock" , "fell" , "It rises" , "Rot on rocky peak" .)