Troublesome, annoying (5)
I believe the answer is:
pesky
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">troublesome</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >'<span class="explanation-format__original">annoying</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that annoying can be written as pesky)</span><br/ ><br/ ></span>
(Other definitions for pesky that I've seen before include "Annoying (informal)" , "Annoying - troublesome" , "Bothersome" .)