trapezoid

/ˌtræpəˈzɔɪd/

/ˈtræpɪzɔɪd/

Other forms: trapezoids

In geometry a trapezoid is a four-sided figure with two sides that are parallel. Imagine taking an equilateral triangle and chopping its tip off so that it's made up of two parallel lines on top and bottom and you've got a trapezoid.

The word trapezoid comes from the Greek trapeza meaning "table" and -oeides meaning "shaped." Think of a trapezoid as table-shaped. It has a pair of parallel sides that are also known as the bases of the figure. To find the area of a trapezoid, take the average of the bases and multiply it by the height. In anatomy, the trapezoid is the smallest of the eight small bones in the wrist.

Definitions of trapezoid

1. noun

   a quadrilateral with one pair of parallel sides
   type of:

   quadrangle, quadrilateral, tetragon

   a four-sided polygon
2. noun

   the wrist bone between the trapezium and the capitate bones
   synonyms: os trapezoideum, trapezoid bone

   type of:

   carpal, carpal bone, wrist bone

   any of the eight small bones of the wrist of primates