A high explosive (8)
I believe the answer is:
dynamite
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">a high explosive</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 dynamite that I've seen before include "High explosive" , "might one be blown away by it?" , "Tiny dame (anag)" , "Spectacular (or dangerous) person (or thing)" , "an exciting thing" .)