Means of ascent (6)
I believe the answer is:
ladder
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">means of ascent</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 ladder that I've seen before include "Means of ascent" , "Set of rungs" , "sometimes with companion" , "Companionway" , "Row of unravelled stitches" .)