Rattle, unnerve (7)
I believe the answer is:
fluster
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">rattle</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">unnerve</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ ></span>
(Other definitions for fluster that I've seen before include "Make hot and flurried." , "Ruffle" , "Agitate" , "Confuse" , "Disconcert" .)