Complain petulantly (5)
I believe the answer is:
whine
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">complain petulantly</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for whine that I've seen before include "Nagging complaint" , "Moan" , "beef?" , "Gripe" , "Complain petulantly" .)