having or contained by two plane faces 二面的 a dihedral angle. 二面角。
noun
an angle formed by two plane faces 二面角 ■[mass noun](Aeronautics)inclination of an aircraft's wing from the horizontal, especially upwards away from the fuselage (航天)(机翼)反角。 比较 anhedral ■(Climbing N. Amer.)a place where two planes of rock meet at an angle of between 60° and 120° (登山 北美)向内的转角,V型裂隙(指岩石的两个面相交成60° 到120°角的地方)
语源
late 18th cent.: from di- 'two' + -hedral (see -hedron)