Scottish valley (4)
I believe the answer is:
glen
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">scottish valley</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 glen that I've seen before include "Campbell perhaps" , "Narrow, deep mountain valley" , "Narrow secluded valley in mountains" , "Narrow valley with a stream" , "Scottish mountain valley" .)