The Collaborative International Dictionary of English v.0.48:

Discussion \Dis*cus"sion\, n. [L. discussio a shaking,
   examination, discussion: cf. F. discussion.]
   1. The act or process of discussing by breaking up, or
      dispersing, as a tumor, or the like. [archaic]
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   2. The act of discussing or exchanging reasons; examination
      by argument; debate; disputation; agitation.
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            The liberty of discussion is the great safeguard of
            all other liberties.                  --Macaulay.
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   Discussion of a problem or Discussion of an equation
      (Math.), the operation of assigning different reasonable
      values to the arbitrary quantities and interpreting the
      result. --Math. Dict.
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