Flash, sparkle (9)
I believe the answer is:
coruscate
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">flash</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">sparkle</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that sparkle can be written as coruscate)</span><br/ ><br/ ></span>
(Other definitions for coruscate that I've seen before include "Show flashes of brilliance" , "Flash, sparkle" , "Glitter or sparkle in court case" , "Shimmer and flash in court case" .)