Definition:Quadrilateral/Trapezium

Definition
A trapezium is a quadrilateral with no parallel sides.


 * Trapezium.png

Linguistic Note
The plural of trapezium is trapezia.

The word comes from Latin, in which language it is a neuter noun of the second declension, hence its plural form.

Also defined as
Outside the US (one of a few countries that use this definition), a trapezium is a quadrilateral which has one pair of sides parallel, that is, what the US defines as a trapezoid.

Also known as
Outside the US (one of a few countries that use this definition), this figure is known as a trapezoid.

In order to reduce confusion, when such a quadrilateral is intended, it is probably better to use the term irregular quadrilateral instead.

Euclid, in his definitions, did not distinguish between trapezia and trapezoids.