Check-writing implement (3)
I believe the answer is:
pen
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">check</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">writing implement</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(pen is a kind of writing implement)</span><br/ ><br/ ></span>
(Other definitions for pen that I've seen before include "record" , "International writers's organisation" , "Cage - bird" , "Swan for the writer" , "Shut up" .)