High Scottish mountain (5)
I believe the answer is:
munro
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">high scottish mountain</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 munro that I've seen before include "Scottish mountain over three-thousand feet" , "One of the Scottish peaks over 3000 feet" , "H H ---, the author 'Saki'" , "One of Scottish mountains over 3000 feet" , "Big Ben" .)