col (saddle point)
A mountain-pass in a @[email protected] is known as a col or @[email protected] It is a point at which the @[email protected] is zero along all coordinates, and the curvature is positive along all but one coordinate, which is the @[email protected], along which the curvature is negative.
PAC, 1996, 68, 149. (A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)) on page 158 [Terms] [Paper]