Definify.com

Webster 1913 Edition

Adj.

[Gr.

δι-

δίσ-

twice + [GREEK] a seat, bottom, base, fr. [GREEK] to sit. Cf.

Having two plane faces;

as, the

dihedral

summit of a crystal

Dihedral angle

the angular space contained between planes which intersect. It is measured by the angle made by any two lines at right angles to the two planes.

Adj.

[Gr., supra; a seat or face.] Having two sides, as a figure.

dihedral ‎(plural dihedrals)

dihedral ‎(not comparable)

(mathematics) Consisting of, relating to or contained between two plane surfaces.
dihedral angle
(of a kite or an aeroplane) Having wings that form a dihedral angle, especially when the angle between the upper sides is less than 180°.
(aviation) Of wing pairs, inclined at an upward angle to each other.