Put to the test (5)
I believe the answer is:
prove
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">put to the test</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 prove that I've seen before include "Ascertain" , "Demonstrate (truth)" , "Demonstrate beyond doubt" , "Show by evidence" , "Show to be true" .)