Filaments (6)
I believe the answer is:
fibres
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">filaments</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 fibres that I've seen before include "They may be spun" , "thin strands or threads" , "Threadlike substances" , "Long slender substances" , "Threadlike structures" .)