Dirk (6)
I believe the answer is:
dagger
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dirk</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 dagger that I've seen before include "Murder weapon" , "'Short, double-edged blade (6)'" , "that has an incisive point" , "''Is this a ... which I see before me'' (Macbeth)" , "A weapon; a reference mark" .)