duct

A duct is not just something builders work with. It is a passage that carries something from one place to another, most often air or liquid. You can think of the metal passages in a house that move warm or cool air, or the small passages in the body that carry fluids. The word comes from the Latin ducere, meaning "to lead." In that sense, a duct is a guided path that helps something reach the right place.

A duct is a tube, pipe, or channel made to carry something along a set path. Many people first think of the metal air passages hidden in walls and ceilings that move heated or cooled air through a building, but the idea is much broader than that. A duct can be any built or natural passageway that guides the movement of gas, liquid, or even cables.

In the body, ducts are important: bile ducts carry digestive fluid from the liver, and tear ducts drain tears from the eyes. In engineering, ducting can also provide a protected and organized route for wiring. The word comes from the Latin ducere, meaning "to lead," and that basic idea still fits the modern meaning well.

Today, the word is mainly used for physical channels, and it is related to words like "conduct" and "induct." In every case, the central idea is leading something from one place to another. Whether it is a metal air passage behind a wall or a tiny pathway in a living thing, a duct is a route that carries something where it needs to go.