Rockies resort (5)
I believe the answer is:
aspen
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">rockies resort</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 aspen that I've seen before include "somewhere in Colorado" , "A poplar with shivering leaves" , "quill-like?" , "Very timid" , "Colorado winter sports town" .)