Saddle Point

Note the nipple points and the cleve point.

In mathematics, a saddle point is a point in the domain of a function that is a stationary point but not a local extremum. The name derives from the fact that the prototypical example in two dimensions is a surface that curves up in one direction, and curves down in a different direction, resembling a saddle or a mountain pass. In terms of contour lines, a saddle point in two dimensions gives rise to a contour that appears to intersect itself.

Read more about Saddle Point:  Mathematical Discussion, Other Uses

Famous quotes containing the words saddle and/or point:

    The dress makes the person; the saddle the horse.
    Chinese proverb.

    No doubt, to a man of sense, travel offers advantages. As many languages as he has, as many friends, as many arts and trades, so many times is he a man. A foreign country is a point of comparison, wherefrom to judge his own.
    Ralph Waldo Emerson (1803–1882)