Quadrilateral figures in which both pairs of opposite sides are parallel to each other, especially used for such figures in which the sides do not intersect at right angles. For four-sided figures having right angles, the terms "square" or "rectangle" are more commonly used. (en)
Vierzijdige figuren waarvan beide overstaande zijden evenwijdig zijn. (nl)
Figuras cuadrilaterales que tienen ambos pares de lados opuestos paralelos al otro. (es)