Is it ensure, insure, or assure?
early 14c., "bed of running water," from Old French chanel "bed of a waterway; tube, pipe, gutter," from Latin canalis "groove, channel, waterpipe" (see canal). Given a broader, figurative sense 1530s (of information, commerce, etc.); meaning "circuit for telegraph communication" (1848) probably led to that of "band of frequency for radio or TV signals" (1928). The Channel Islands are the French Îles Anglo-Normandes.
1590s, "to wear channels in," from channel (n.). Meaning "convey in a channel" is from 1640s. Related: Channeled; channeling.
A vein, usually in the crook of the elbow or the instep, favored for the injection of narcotics; main line (1950s+ Narcotics)verb
(1.) The bed of the sea or of a river (Ps. 18:15; Isa. 8:7). (2.) The "chanelbone" (Job 31:22 marg.), properly "tube" or "shaft," an old term for the collar-bone.