quadrilateral

adj. four-sided, having four sides; square

n. square; quadrilateral, four-sided and four-angled plane figure (Geometry); area of land between four fortresses

In geometry, a quadrilateral is a polygon with four sides or edges and four vertices or corners. Sometimes, the term quadrangle is used, for etymological symmetry with triangle, and sometimes tetragon for consistency with pentagon (5 sided), hexagon (6 sided) and so on.Quadrilaterals are either simple (not self-intersecting) or complex (self-intersecting). Simple quadrilaterals are either convex or concave.
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Noun
1. a four-sided polygon
(synonym) quadrangle, tetragon
(hypernym) polygon, polygonal shape
(hyponym) parallelogram
Adjective
1. having four sides
(synonym) four-sided
(similar) multilateral, many-sided

adj. quadrilateral, four-sided

adj. quadrilateral, square