i Register
In some senses, rectangle is marked as archaic. Watch for register when choosing this word.
noun
Any quadrilateral having opposing sides parallel and four right angles.
Such a quadrilateral that is oblong (longer than it is wide): one that is not regular (equilateral), that is, any except a square.
A 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?
The 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.
adj
Right-angled.
a rectangle triangle