duct /dʌkt/ BrE AmE noun [countable]
[ Date: 1600-1700 ; Language: Latin ; Origin: ductus , from ducere 'to lead' ]
1 . a pipe or tube that liquids, air, ↑ cable s etc pass through:
Air is heated and then circulated through large ducts to all parts of the house.
2 . a narrow tube in your body or in a plant that liquid passes through:
a tear duct