Point of inflection

Inflection \In*flec"tion\, n. [L. inflexio : cf. F. inflexion.
   See {Inflect}.] [Written also {inflecxion}.]
   1. The act of inflecting, or the state of being inflected.
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   2. A bend; a fold; a curve; a turn; a twist.
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   3. A slide, modulation, or accent of the voice; as, the
      rising and the falling inflection.
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   4. (Gram.) The variation or change which words undergo to
      mark case, gender, number, comparison, tense, person,
      mood, voice, etc.
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   5. (Mus.)
      (a) Any change or modification in the pitch or tone of the
          voice.
      (b) A departure from the monotone, or reciting note, in
          chanting.
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   6. (Opt.) Same as {Diffraction}.
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   {Point of inflection} (Geom.), the point on opposite sides of
      which a curve bends in contrary ways.
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