Fill in the blank to complete the definition. has only one pair of opposite sides that are parallel.

A trapezoid has only one pair of opposite sides that are parallel. This four-sided shape, also known as a trapezium in some regions, comes in different varieties like isosceles trapezoids, where the non-parallel sides are equal in length, adding to its uniqueness. Trapezoids can be found in various real-world applications, such as in architecture and engineering, where they are used in the design of roofs, bridges, and even furniture. Their distinct shape can offer aesthetic appeal while also providing structural benefits, making them a favorite among designers and builders alike.