Let it all out
I believe the answer is:
vent
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">let it all out</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for vent that I've seen before include "pipe" , "Slit in the back of a jacket" , "Small outlet" , "Opening for air/gas" , "Give outlet as to feelings" .)