Code word for S (6)
I believe the answer is:
sierra
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">code word for s</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 sierra that I've seen before include "Mountain range -- code word for S" , "A Spanish mountain chain (6)" , "Vehicle" , "Mountain range in Spanish-speaking countries" , "Spanish range of mountains" .)