Persistently annoying (5)
I believe the answer is:
pesky
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">persistently annoying</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for pesky that I've seen before include "Annoying - troublesome" , "Bothersome" , "Annoying (informal)" .)