The Collaborative International Dictionary of English v.0.48:

Channel \Chan"nel\ (ch[a^]n"n[e^]l), n. [OE. chanel, canel, OF.
   chanel, F. chenel, fr. L. canalis. See Canal.]
   1. The hollow bed where a stream of water runs or may run.
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   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.
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   3. (Geog.) A strait, or narrow sea, between two portions of
      lands; as, the British Channel.
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   4. That through which anything passes; a means of passing,
      conveying, or transmitting; as, the news was conveyed to
      us by different channels.
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            The veins are converging channels.    --Dalton.
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            At best, he is but a channel to convey to the
            National assembly such matter as may import that
            body to know.                         --Burke.
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   5. A gutter; a groove, as in a fluted column.
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   6. pl. [Cf. Chain wales.] (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.
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   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.
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   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.
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   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.
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   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.
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   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.
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   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 Nov[ae]hollandi[ae].

   Channel goose. (Zool.) See Gannet.
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