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:
“It is beautiful to remember that he passed away as he wished, in the saddle riding hard.”
—Lyndon Baines Johnson (1908–1973)
“A route differs from a road not only because it is solely intended for vehicles, but also because it is merely a line that connects one point with another. A route has no meaning in itself; its meaning derives entirely from the two points that it connects. A road is a tribute to space. Every stretch of road has meaning in itself and invites us to stop. A route is the triumphant devaluation of space, which thanks to it has been reduced to a mere obstacle to human movement and a waste of time.”
—Milan Kundera (b. 1929)