Dihedral or polyhedral may refer to:

• Dihedral angle, the angle between two mathematical planes
• Dihedral (aeronautics), the upward angle of a fixed-wing aircraft's wings where they meet at the fuselage, dihedral effect of an aircraft, longitudinal dihedral angle of a fixed-wing aircraft
• Dihedral group, the group of symmetries of the n-sided polygon in abstract algebra
  • Also Dihedral symmetry in three dimensions
• Dihedral kite, also known as a bowed kite
• Dihedral doors, also known as butterfly doors
• Dihedral prime, also known as a dihedral calculator prime
• In rock climbing, an inside corner of rock

• Anhedral (disambiguation)
• Euhedral, a crystal structure
• Polyhedron, a geometric shape