Secluded narrow valley (4)
I believe the answer is:
glen
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">secluded narrow valley</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 glen that I've seen before include "Depression in Scotland" , "Narrow, deep mountain valley" , "Scottish mountain valley" , "Campbell perhaps" , "Scottish or Irish valley" .)