Central highway (5)
I believe the answer is:
aorta
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">central highway</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 aorta that I've seen before include "Main artery from heart" , "sort of vessel" , "it's drawing blood!" , "Main arterial vessel, carrying blood to the heart" , "Blood carrier" .)