from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. curved in opposite ways in two directions; saddle-shaped
- adj. of a surface whose Gaussian curvature is negative at all points
from the GNU version of the Collaborative International Dictionary of English
- adj. Having opposite curvatures, that is, curved longitudinally in one direction and transversely in the opposite direction, as the surface of a saddle.
from The Century Dictionary and Cyclopedia
- An epithet descriptive of the curvature of a surface, such as that of a saddle or the inner surface of an anchor-ring, which intersects its tangent-plane at the point of contact, and bends away from it, partly on one side of it and partly on the other, and has thus in some of its normal sections curvatures oppositely directed to those in others.
Sorry, no etymologies found.
The saddle-shaped structure is also known as a hyperbolic paraboloid surface, or an anticlastic surface.
Negative Poisson's ratio in plane may also make draping of prepregs easier because they will naturally form synclastic curvatures (dome shapes) as opposed to anticlastic curvatures (saddle shapes) like positive PR versions.
Both of these anticlastic bracelets, made by David Mayer, are indicitive of the organic, natural shapes that characterize the artist's work.