canal n.

late 14c., "long slender woody stem," from Old French cane "reed, cane, spear" (13c., Modern French canne), from Latin canna "reed, cane," from Greek kanna, perhaps from Babylonian-Assyrian qanu "tube, reed" (compare Hebrew qaneh, Arabic qanah "reed"), which may come from Sumerian-Akkadian gin "reed." The sense of "length of cane used as a walking stick" is from 1580s.

early 14c., "bed of a stream of water," from Old French chanel "bed of a waterway; tube, pipe, gutter," from Latin canalis "groove, channel, waterpipe" (see canal). The English word was given a broader, figurative sense by 1530s: "that by which something passes or is transmitted" (in reference to information, commerce, etc.); the meaning "circuit for telegraph communication" (1848) probably led to that of "band of frequency for radio or TV signals" (1928). Also "part of a sea making a passageway between land masses, a large strait" (1550s).