Audible exhalation (4)
I believe the answer is:
sigh
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">audible exhalation</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 sigh that I've seen before include "Moan softly" , "Exhale wearily" , "Exhale deeply" , "Sound of despondency" , "Audible breath expressing weariness" .)