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n. Mathematics A polygon having four sides.

adj. Having four sides.

n. a polygon having four sides.

adj. having four sides.

adj. Having four sides, and consequently four angles; quadrangular.

n. A plane figure having four sides, and consequently four angles; a quadrangular figure; any figure formed by four lines.

n. An area defended by four fortresses supporting each other.

Having four sides; composed of four lines.

n. A figure formed of four Straight lines.

n. Milit., the space inclosed between, and defended by, four fortresses: as, the Bulgarian quadrilateral. The most famous quadrilateral was that in northern Italy, inclosed by the fortresses of Peschiera, Mantua, Verona, and Legnago.

adj. having four sides

n. a four-sided polygon

"For instance, the term quadrilateral, or four-sided rectilinear figure, is correctly divided into square, oblong, rhombus, rhomboid and trapezium."

multilateral    many-sided   

inscriptible quadrilateral    heronic cyclic    circumscriptible quadrilateral    plane quadrilateral    skew quadrilateral    quadrilateral map-projection    quadrilateral construction    cyclic quadrilateral   

quadrangular   

face-centered    tetrahedral    trapezoid    six-sided    eidolon    octangular    square-based    three-sided    well-like    open-plan