Trapezoid

The trapezoid, or traz, is a quadrilateral with one pair of opposite parallel sides. It is a specific case of an irregular tetragon.

Types of trapezoids
If the two non-parallel sides of a trapezoid intersect, the figure may more specifically be called a crossed trapezoid. If the two non-parallel sides have the same length, the figure may be called an isosceles trapezoid. If both conditions are met, the figure may be called a crossed isosceles trapezoid, or simply a butterfly.