Trapezoid

In geometry, A trapezoid (in North America) or trapezium (in Britain and elsewhere) is a quadrilateral, which is defined as a shape with four sides. This shape has two parallel sides which are called the bases of the trapezoid, and another two sides called its legs. In North America, the term "trapezium" is used for what is elsewhere called an irregular quadrilateral, which has no parallel sides.^[1]

1. ↑ "1913 American definition of trapezium". Merriam-Webster Online Dictionary. Retrieved 2007-12-10.