Climb; upward slope (6)
I believe the answer is:
ascent
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">climb</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that climb can be written as ascent)</span><br/ ><br/ >'<span class="explanation-format__original">upward slope</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ ></span>
(Other definitions for ascent that I've seen before include "A rise in status; climb" , "The climbing of a peak" , "Upwards motion" , "Enacts in climb" , "Upward slope" .)