Definition of "dihedral"

(mathematics) An angle between two plane surfaces  examples

(aeronautics) The upward slope of an aircraft's wing  examples

(chemistry) The angle between pairs of chemical bonds separated by a third bond  examples

(mathematics) Consisting of, relating to or contained between two plane surfaces.  examples

(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°.  examples

(aviation) Of wing pairs, inclined at an upward angle to each other.  examples