Barked in a high-pitched tone (6)
I believe the answer is:
yapped
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">barked in a high-pitched tone</span>' is the definition.<br/ ><span class="explanation-format__explanation">('yap' can be a synonym of 'bark in a high-pitched tone')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for yapped that I've seen before include "Barked like a small dog" , "Chatted" , "Yelped" .)