Pen part (3)
I believe the answer is:
nib
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">pen part</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 nib that I've seen before include "Part of a fountain pen" , "Writing tip of old pen" , "Pen-tip" , "Pen-point" , "Pen end" .)