Quadrangle n. : A plane figure having four angles, and consequently four sides; any figure having four angles.

Quadrangle n. : A square or quadrangular space or inclosure, such a space or court surrounded by buildings, esp. such a court in a college or public school in England.

Example:
How do I draw a Quadrangle that has 2 pairs of equal sides but is not a parallelogram?

Taxonomy
Quadrangle Group LLC, Private Investment Firm, Leveraging, Relationships, Firm Overview, Global Locations.

Defination from the web:
Invests in mature and high growth media and communications companies in the United States and Europe.