rectangle

plural rectangles

1. geometryAny quadrilateral having opposing sides parallel and four right angles.
2. Such a quadrilateral that is oblong (longer than it is wide): one that is not regular (equilateral), that is, any except a square.
3. archaicA right angle.

   For why should you praise, for example, the integrity of a Square who faithfully defends the interests of his client, when you ought in reality rather to admire the exact precision of his Rectangles?

   1884, A Square [pseudonym; Edwin A. Abbott], Flatland […] , London: Seeley & Co., Part I: This World, § 12.— Of the Doctrine of our Priests, page 46

4. archaicThe product of two quantities.

   In Lines it [the product] is always (and ſometimes in Numbers) call'd the Rectangle between the two Lines, multiply'd by one another.

   1728, E[phraim] Chambers, “Product”, in Cyclopædia: Or, An Universal Dictionary of Arts and Sciences; […] In Two Volumes, volumes II (I–Z), London: […] James and John Knapton [et al.], →OCLC, page 886, column 1

1. archaicnot comparableRight-angled.

   a rectangle triangle