dihedral angle

noun

, Geometry.

1. the angle between two planes in a dihedron.
2. dihedron.

Word History and Origins

Origin of dihedral angle¹

First recorded in 1820–30

Example Sentences

Kedlaya, Poonen and two other co-authors proved that exactly 59 isolated examples plus two infinite families of tetrahedra have rational dihedral angles.

From Quanta Magazine

In 1995, two of the authors of the new work, Poonen and Rubinstein, actually found what ultimately turned out to be every tetrahedron with rational dihedral angles.

From Quanta Magazine

To find the desired ones, with all rational dihedral angles, Conway and Jones said that mathematicians needed to find a special class of solutions to the equation, which would correspond exactly to the rational tetrahedra.

From Quanta Magazine

In determining the center of gravity, the bird was frozen in the soaring position, its wings making a dihedral angle of 150.

From Project Gutenberg

At this point in Book VI it is customary to introduce the dihedral angle.

From Project Gutenberg

The reason is that the flexible covering will be bowed back by the wind, forming an approximate "dihedral angle."

From Project Gutenberg

The wings were fixed at a considerable dihedral angle, and the engine was a twenty-four horse-power Antoinette.

From Project Gutenberg

But in some machines to-day a modified dihedral angle is used, and with satisfactory results.

From Project Gutenberg