Material for violin strings (6)
I believe the answer is:
catgut
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">material for violin strings</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for catgut that I've seen before include "Traditional violin string" , "Strong cord used in surgery and violin strings" , "Material used for violin strings, for example" , "Strong cord for stitches, etc" , "Natural material for violin strings" .)