In geometry, a **square** is a regular quadrilateral. This means that it has four equal sides and four equal angles (90-degree angles, or right angles). It can also be defined as a rectangle in which two adjacent sides have equal length. A square with vertices ABCD would be denoted *ABCD*.

The square is the n=2 case of the families of n-hypercubes and n-orthoplexes.

Read more about Square: Characterizations, Perimeter and Area, Coordinates and Equations, Construction, Properties, Other Facts, Non-Euclidean Geometry, Graphs

### Famous quotes containing the word square:

“This house was designed and constructed with the freedom of stroke of a forester’s axe, without other compass and *square* than Nature uses.”

—Henry David Thoreau (1817–1862)

“I walked by the Union *Square* Bar, I was gonna go in. And I saw myself, my reflection in the window. And I thought, “I wonder who that bum is.” And then I saw it was me. Now look at me, I’m a bum. Look at me. Look at you. You’re a bum.”

—J.P. (James Pinckney)

“Mark you the floore? that *square* & speckled stone,

Which looks so firm and strong,

Is Patience:”

—George Herbert (1593–1633)