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

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 snakes fangs

[ Syn: duct , epithelial duct , channel ]

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

provide (a city) with a canal

[ Syn: canalize , canalise ]