What is "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.

2. A bend; a fold; a curve; a turn; a twist.

3. A slide, modulation, or accent of the voice; as, the rising and the falling inflection.

4. (Gram.) The variation or change which words undergo to mark case, gender, number, comparison, tense, person, mood, voice, etc.

5. (Mus.)

   1. Any change or modification in the pitch or tone of the voice.

   2. A departure from the monotone, or reciting note, in chanting.

6. (Opt.) Same as Diffraction.

   Point of inflection (Geom.), the point on opposite sides of which a curve bends in contrary ways.

alt. (context mathematics English) a point on a curve at which the sign of the curvature changes; at this point the second derivative of the underlying function will be zero, but positive on one side and negative on the other. n. (context mathematics English) a point on a curve at which the sign of the curvature changes; at this point the second derivative of the underlying function will be zero, but positive on one side and negative on the other.