Duck sound (5)
I believe the answer is:
quack
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">duck sound</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 quack that I've seen before include "Duck's cry or dud doctor" , "Charlatan - cry of duck" , "Noise of a duck" , "Unqualified man" , "may get called across the pond" .)