Mortarboard attachment (6)
I believe the answer is:
tassel
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">mortarboard attachment</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for tassel that I've seen before include "Grapefruit and tangerine hybrid" , "Decorative bunch of cords" , "Decorative hanging tuft" , "Hanging tuft of threads" , "male hawk" .)