Definition of ducts:
(n) :
A pipe, tube or canal which carries gas or liquid from one place to another.
(n) :
An enclosure or channel for electrical cable runs, telephone cables, or other conductors.
(n) :
(anatomy) A vessel for conveying lymph or glandular secretions such as tears or bile.
(n) :
(botany) A tube or elongated cavity (such as a xylem vessel) for conveying water, sap, or air.
(v) :
(transitive) To channel something (such as a gas) or propagate something (such as radio waves) through a duct or series of ducts.
(n) :
(physics) A layer (as in the atmosphere or the ocean) which occurs under usually abnormal conditions and in which radio or sound waves are confined to a restricted path.