Burp (5)
I believe the answer is:
belch
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">burp</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for belch that I've seen before include "Vent air from the stomach through the mouth" , "Violently eject" , "Expel gas through the mouth" , "Eructation" , "Forcibly expel" .)