Sinuous, winding (6)
I believe the answer is:
twisty
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">sinuous</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >'<span class="explanation-format__original">winding</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ ></span>
(Other definitions for twisty that I've seen before include "requiring one to take turns" , "Sinuous" , "Windy" , "Convoluted" , "Bendy, curly" .)