1400-50;late Middle English: waterpipe, tubular passage < Latincanālis, perhaps equivalent to can(na) reed, pipe (see cane) + -ālis-al1; def. 5 a mistranslation of Italiancanali channels, term used by G. V. Schiaparelli
an artificial waterway constructed for navigation, irrigation, water power, etc
any of various tubular passages or ducts the alimentary canal
any of various elongated intercellular spaces in plants
(astronomy) any of the indistinct surface features of Mars originally thought to be a network of channels but not seen on close-range photographs. They are caused by an optical illusion in which faint geological features appear to have a geometric structure
early 15c., from Fr. canal (12c.), noun use of an adj., from L. canalis "water pipe, groove, channel," from canna "reed." Originally "a pipe for liquid," its sense transfered by 1670s to "artificial waterway."