canal (noun)

(astronomy) an indistinct surface feature of Mars once thought to be a system of channels; they are now believed to be an optical illusion

duct, epithelial duct, canal, channel (noun)

a bodily passage or tube lined with epithelial cells and conveying a secretion or other substance

"the tear duct was obstructed"; "the alimentary canal"; "poison is released through a channel in the snake's fangs"

canal (verb)

long and narrow strip of water made for boats or for irrigation

canal, canalize, canalise (verb)

provide (a city) with a canal

canal (Noun)

An artificial waterway, often connecting one body of water with another

canal (Noun)

A tubular channel within the body.

canal (Verb)

To dig an artificial waterway in or to (a place), especially for drainage

canal (Verb)

To travel along a canal by boat

Canal

Canals are man-made channels for water. There are two types of canal: ⁕Waterways: navigable transportation canals used for carrying ships and boats shipping goods and conveying people, further subdivided into two kinds: ⁕Those connected to existing lakes, rivers, or oceans. Included are inter-basin canals, such as the Suez Canal, Erie Canal, and the Panama Canal. ⁕Those connected in a city network: such as the Canal Grande and others of Venice Italy; the gracht of Amsterdam, and the waterways of Bangkok. ⁕Aqueducts: water supply canals that are used for the conveyance and delivery of potable water for human consumption, municipal uses, and agriculture irrigation. Rills and acequias are small versions.

Canal

Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow under atmospheric pressure, and can be thought of as artificial rivers. In most cases, a canal has a series of dams and locks that create reservoirs of low speed current flow. These reservoirs are referred to as slack water levels, often just called levels. A canal can be called a navigation canal when it parallels a natural river and shares part of the latter's discharges and drainage basin, and leverages its resources by building dams and locks to increase and lengthen its stretches of slack water levels while staying in its valley. A canal can cut across a drainage divide atop a ridge, generally requiring an external water source above the highest elevation. The best-known example of such a canal is the Panama Canal. Many canals have been built at elevations, above valleys and other waterways. Canals with sources of water at a higher level can deliver water to a destination such as a city where water is needed. The Roman Empire's aqueducts were such water supply canals.