Give vent to (3)
I believe the answer is:
air
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">give vent to</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 air that I've seen before include "Expose" , "Outward appearance" , "Atmosphere, manner" , "Spread publicity" , "Means of travelling" .)