Nasal explosion (6)
I believe the answer is:
sneeze
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">nasal explosion</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 sneeze that I've seen before include "Prelude to Bless you!" , "Explosion of air through nose and mouth" , "symptom of flu" , "Symptom of cold" , "To which gesundheit is often a response" .)