Definition of trapezoid in English:



  • 1North American A quadrilateral with only one pair of parallel sides.

    • ‘He arranges thin rectangles, squares, triangles and trapezoids in complex patterns on the wall.’
    • ‘The key elements of our total approach include measurements, models, and data, which are represented by the black squares, trapezoids, and ellipses respectively.’
    • ‘With their vast knowledge of geometry, they were able to correctly calculate the areas of triangles, rectangles, and trapezoids and the volumes of figures such as bricks, cylinders, and pyramids.’
    • ‘For example, Angel consists of three layers of open triangles, trapezoids, parallelograms and pentagons, once again made of wood.’
    • ‘Wood blinds, meanwhile, can fit a variety of applications, including quarter arches, full arches, angles, trapezoids, hexagons and triangles.’
    1. 1.1British A quadrilateral with no sides parallel.
      Compare with trapezium
      • ‘He has invented the trisosceles trapezoid (or trapezium as we say in the UK).’
      • ‘The bold monochrome panels in other works, such as the juxtaposed trapezoids in the Birds Over Loop pieces, are reminiscent of Sean Scully's paintings.’
      • ‘It is also relatively easy to make, as long as you don't get too fussed about perfect trapezoids of bread and the delicate art of construction.’
      • ‘It is not an easy show: a dozen works on paper, single coloured trapezoids, subtle curves and rhomboids, hung sparely in a stark white interior.’
  • 2Anatomy
    A small carpal bone in the base of the hand, articulating with the metacarpal of the index finger.

    • ‘Climbing mostly builds muscles that pull (forearms, lats, trapezoids, biceps) while demanding less of those that push (shoulders, pectorals, triceps).’
    • ‘During surgery, we observed partial or complete detachment of the trapezoid and deltoid muscles from the lateral clavicle in all patients.’
    • ‘Complete dislocation of the acromioclavicular joint with avulsion of the trapezoid and deltoid muscle results in a decrease in upper extremity strength.’
    • ‘The distal row of carpals includes the hamate, capitate, trapezium, and trapezoid, which are closely approximated to the metacarpals.’
    • ‘A mass of muscle would pop up: deltoids would ripple, trapezoids bunch and gloots clench.’


Early 18th century: from modern Latin trapezoides, from late Greek trapezoeidēs, from trapeza ‘table’ (see trapezium).