Quadrilateral vs. Trapezoid — What's the Difference?

A quadrilateral is a polygon in Euclidean plane geometry with four edges (sides) and four vertices (corners). Other names for quadrilateral include quadrangle (in analogy to triangle) and tetragon (in analogy to, e.g., pentagon or hexagon).

In Euclidean geometry, a convex quadrilateral with at least one pair of parallel sides is referred to as a trapezium () in English outside North America, but as a trapezoid () in American and Canadian English. The parallel sides are called the bases of the trapezoid and the other two sides are called the legs or the lateral sides (if they are not parallel; otherwise there are two pairs of bases).

A polygon having four sides.

A quadrilateral having two parallel sides.

Having four sides.

Chiefly British A trapezium.

A polygon with four sides.

(Anatomy) A small bone in the wrist, situated near the base of the index finger.

An area defended by four fortresses supporting each other.

(Sports) An area in the shape of a trapezoid marked behind the goal line and the goal in ice hockey, where the goalie is allowed to play the puck.

Having four sides.

A (convex) quadrilateral with two (non-adjacent) parallel sides.

Having four sides, and consequently four angles; quadrangular.

A convex quadrilateral with no sides parallel.

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

(anatomy) The trapezoid bone of the wrist.

An area defended by four fortresses supporting each other; as, the Venetian quadrilateral, comprising Mantua, Peschiera, Verona, and Legnano.

A plane four-sided figure, having two sides parallel to each other.

A four-sided polygon

A bone of the carpus at the base of the second metacarpal, or index finger.

Having four sides

Having the form of a trapezoid; trapezoidal; as, the trapezoid ligament which connects the coracoid process and the clavicle.

Of or pertaining to the trapezoid ligament; as, the trapezoid line.

A quadrilateral with two parallel sides

The wrist bone between the trapezium and the capitate bones