Definition of trihedral in English:



  • (of a solid figure or body) having three sides or faces (in addition to the base or ends); triangular in cross section.

    • ‘This German-made touring kayak uses a trihedral hull design to gain a unique balance of glide speed, carving agility, carrying capacity, stability, and comfort.’
    • ‘It is fascinating to look at the dihedral angles in trihedral acrons and compare those acrons which have been resolved with those that have not.’
    • ‘These results clearly demonstrate that the trihedral twist reflector of the invention produces an acceptable and usable cross polarized echo over a wide range of angles and frequencies.’
    • ‘Iceberg targets are known to have a combined surface and volume scattering mechanism while ships tend to have a combination of dihedral and trihedral surface scattering.’
    • ‘Recently. sea-scatter data was collected from 1.9-11.5 GHz with trihedral reflectors.’
    • ‘Different trihedral angle configurations were generated using synthetic data for testing the authors’ approach of finding object orientation by angle to angle constraint.’
    • ‘The other uses the trihedral corner reflector and the natural distributed targets.’


  • A trihedral figure.

    • ‘One of the most interesting novelties of the volume was the so-called ‘moving trihedrals’ for twisted curves as well as surfaces so freely used in writings of Darboux and others.’
    • ‘Radar corner reflectors are simple trihedrals of aluminium that strongly reflect the radar signal back to the satellite.’
    • ‘The right-left ambiguity ratio, measured using 5-m trihedrals on both sides of the flight track, is about 10 dB for a single antenna element on receive.’
    • ‘The mechanical mounting of the pod underneath the carrier aircraft ensures parallelism of the corresponding trihedrals with limited precision.’
    • ‘Reference targets that are supported include spheres, flat plates, square dihedrals and trihedrals, and circular cylinders.’
    • ‘Similar substitutions convert the first law of cosines for trihedrals into the law of cosines for the sides of spherical triangles.’


Late 18th century from Greek tri- ‘three’ + hedra ‘base’ + -al.