Definitions for: Quadrilateral
[n] a four-sided polygon
[adj] having four sides
Webster (1913) Definition: Quad`ri*lat"er*al, a. [L. quadrilaterus: cf. F.
quadrilat[`e]re, quadrilat['e]ral. See Quadri- and
Having four sides, and consequently four angles;
1. (Geom.) A plane figure having four sides, and consequently
four angles; a quadrangular figure; any figure formed by
2. An area defended by four fortresses supporting each other;
as, the Venetian quadrilateral, comprising Mantua,
Peschiera, Verona, and Legnano.
Complete quadrilateral (Geom.), the figure made up of the
six straight lines that can be drawn through four points,
A, B, C, I, the lines being supposed to be produced
Synonyms: four-sided, many-sided, multilateral, quadrangle, tetragon
See Also: parallelogram, polygon, polygonal shape, trapezium, trapezoid