Sole supporter? (5)
I believe the answer is:
cleat
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sole supporter?</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 cleat that I've seen before include "Device on which to secure a rope" , "Projection for a rope on board" , "Strip used to strengthen a surface to which it is attached" , "One to fasten rope to" , "Projection to tie a rope around" .)