二面角，上反角的英文

• angle， dihedral

• 上:    upper; up; upward
• 反:    reverse side
• 角:    role; part; character
• 上反角:    anhedral angle; dihedral of angle; lateral dihedral angle; positive dihedral; upward dihedral
• 二面角:    angle, dihedral; dihedral angle; interfacial angle