Channel n. 1.The hollow bed where a stream of water runs or may run.
2.The deeper part of a river, harbor, strait, etc., where the main current flows, or which affords the best and safest passage for vessels.
3.(Geog.) A strait, or narrow sea, between two portions of lands; as, the British Channel.
4.That through which anything passes; a means of passing, conveying, or transmitting; as, the news was conveyed to us by different channels. "The veins are converging channels." "At best, he is but a channel to convey to the National assembly such matter as may import that body to know."
5.A gutter; a groove, as in a fluted column.
6.pl. (Naut.) Flat ledges of heavy plank bolted edgewise to the outside of a vessel, to increase the spread of the shrouds and carry them clear of the bulwarks.
7.pl. Official routes of communication, especially the official means by which information should be transmitted in a bureaucracy; as, to submit a request through channels; you have to go through channels.
8.A band of electromagnetic wave frequencies that is used for one-way or two-way radio communication; especially, the frequency bands assigned by the FTC for use in television broadcasting, and designated by a specific number; as, channel 2 in New York is owned by CBS.
9.One of the signals in an electronic device which receives or sends more than one signal simultaneously, as in stereophonic radios, records, or CD players, or in measuring equipment which gathers multiple measurements simultaneously.
10.(Cell biology) An opening in a cell membrane which serves to actively transport or allow passive transport of substances across the membrane; as, an ion channel in a nerve cell.
11.(Computers) A path for transmission of signals between devices within a computer or between a computer and an external device; as, a DMA channel.
Channel bar, Channel iron (Arch.), an iron bar or beam having a section resembling a flat gutter or channel.
Channel bill (Zool.), a very large Australian cuckoo (Scythrops Novaehollandiae.
Channel goose. (Zool.) See Gannet. 
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