Demonstration (4)
I believe the answer is:
show
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">demonstration</span>' is the definition.<br/ ><span class="explanation-format__explanation">(show is a kind of demonstration)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for show that I've seen before include "Musical featuring 'Old Man River'" , "plausible?" , "Demonstration" , "Prove; exhibit" , "charade" .)