Trachea (8)
I believe the answer is:
windpipe
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">trachea</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for windpipe that I've seen before include "The trachea is another name for this breathing passage" , "The trachea, less formally" , "Common name for the trachea" , "It conveys air from the larynx to the lungs" , "Principal passage by which air reaches lungs" .)