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.
“Parents who want a fresh point of view on their furniture are advised to drop down on all fours and accompany the nine or ten month old on his rounds. It is probably many years since you last studied the underside of a dining room chair. The ten month old will study this marvel with as much concentration and reverence as a tourist in the Cathedral of Chartres.”
—Selma H. Fraiberg (20th century)