Real Dictionary

duct
countable noun: A duct is a pipe, tube, or channel which carries a liquid or gas.
countable noun: A duct is a tube in your body which carries a liquid such as tears or bile.

duct in American English
a tube, channel, or canal through which a gas or liquid moves
noun: any tube, canal, pipe, or conduit by which a fluid, air, or other substance is conducted or conveyed
transitive verb: to convey or channel by means of a duct or ducts

duct in British English
noun: a tube, pipe, or canal by means of which a substance, esp a fluid or gas, is conveyed

duct in Chemical Engineering
noun: A duct is a pipe which carries a fluid at low pressures.

duct in Electrical Engineering
noun: A duct is a channel or pipe carrying electric cable or wires.

duct in Mechanical Engineering
noun: A duct is a pipe used to carry fluids at low pressures.