Anticlastic vs. Synclastic — What's the Difference?

(of a surface) curved in opposite ways in two directions; saddle-shaped

(of a surface) curved toward the same side in all directions

(mathematics) of a surface whose Gaussian curvature is negative at all points

(mathematics) of a surface whose Gaussian curvature is positive at all points

Having opposite curvatures, that is, curved longitudinally in one direction and transversely in the opposite direction, as the surface of a saddle.

Curved toward the same side in all directions; - said of surfaces which in all directions around any point bend away from a tangent plane toward the same side, as the surface of a sphere; - opposed to anticlastic.