## Quadrilateral - Wikipedia

In Euclidean plane geometry, a quadrilateral is a polygon with four edges (or sides) and four vertices or corners. Sometimes, the term quadrangle is used, by analogy with triangle, and sometimes tetragon for consistency with pentagon (5-sided) and hexagon (6-sided), or 4-gon for consistency with k-gons for arbitrary values of k.. The word "quadrilateral" is derived from the Latin words quadri ...