Duct (noun)

1. A tube or canal for conveying air, liquids, or substances in a factory or building.
2. An anatomical tube or channel in an animal or plant through which substances such as blood or sap are conveyed.
3. A pipe or channel for conveying water, gas, or sewage.

Origin:

Late 16th century (denoting a canal or conduit for water): from latin ductus 'a leading, guiding', from ducere 'to lead'.

Examples:

1. The air conditioning ducts were clogged with dust and debris, reducing their efficiency.
2. The ducts in the leaf carry sap from the roots to the rest of the plant.
3. The ducts in the building were designed to carry heat and hot water to each unit.
4. Surgeons opened the ducts to remove the blockages and restore normal drainage.
5. The ducts in the city's sewage system were upgraded to prevent overflowing and contamination.