The Collaborative International Dictionary of English v.0.48:

Climax \Cli"max\, n. [L., from Gr. ? ladder, staircase, fr. ? to
   make to bend, to lean. See Ladder, Lean, v. i.]
   1. Upward movement; steady increase; gradation; ascent.
      --Glanvill.
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   2. (Rhet.) A figure in which the parts of a sentence or
      paragraph are so arranged that each succeeding one rises
      above its predecessor in impressiveness.
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            "Tribulation worketh patience, patience experience,
            and experience hope" -- a happy climax. --J. D.
                                                  Forbes.
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   3. The highest point; the greatest degree.
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            We must look higher for the climax of earthly good.
                                                  --I. Taylor.
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   To cap the climax, to surpass everything, as in excellence
      or in absurdity. [Colloq.]
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