Further up (6)
I believe the answer is:
higher
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">further up</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for higher that I've seen before include "More lofty" , "Superior or taller" , "More exalted" , "More elevated" , "Loftier" .)