Not sharp (5)
I believe the answer is:
blunt
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">not sharp</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for blunt that I've seen before include "Frank and forthright" , "Forthright in manner" , "Dull or tactless" , "Dull - outspoken - spy" , "Frank - Soviet spy, d. 1983" .)