Steep or rugged rock face (4)
I believe the answer is:
crag
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">steep</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">rugged rock face</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ ></span>
(Other definitions for crag that I've seen before include "Steep rocky cliff" , "Steep, overhanging rock" , "Rugged rock face" , "Steep rock, peak" , "Rocky hilltop" .)