Sound of a pigeon (3)
I believe the answer is:
coo
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sound of a pigeon</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for coo that I've seen before include "Sound like a dove" , "Speak fondly" , "Dove's noise" , "well I never!" , "Breathe" .)