Parallol 

to laugh out loud along with another person(s) for the same reason at the same time.

We saw our mate come towards from across the carpark, he began to 'hop' over the small boundary wall, however, he fell in doing so. My friend and I really did parallol at the sight of it. Especially because he deserved it, the kant.

Parallol by g'lock June 8, 2016

Parallelogram 

In Euclidean geometry, a parallelogram is a simple (non self-intersecting) quadrilateral with two pairs of parallel sides. The opposite or facing sides of a parallelogram are of equal length and the opposite angles of a parallelogram are of equal measure. The congruence of opposite sides and opposite angles is a direct consequence of the Euclidean Parallel Postulate and neither condition can be proven without appealing to the Euclidean Parallel Postulate or one of its equivalent formulations. The three-dimensional counterpart of a parallelogram is a parallelepiped.

The etymology (in Greek παραλληλ-όγραμμον, a shape "of parallel lines") reflects the definition.

A simple (non self-intersecting) quadrilateral is a parallelogram if and only if any one of the following statements is true:12

Two pairs of opposite sides are equal in length.

Two pairs of opposite angles are equal in measure.

The diagonals bisect each other.

One pair of opposite sides are parallel and equal in length.

Adjacent angles are supplementary.

Each diagonal divides the quadrilateral into two congruent triangles.

The sum of the squares of the sides equals the sum of the squares of the diagonals. (This is the parallelogram law.)

It has rotational symmetry of order 2.

What are you studying Jane?
Oh, I am studying quadrilaterals, specifically I am on Chapter 5 proving a quadrilateral is a Parallelogram, Claire.

Parallelogram by david faustino December 18, 2012

parallel partying 

When Drinkers and Stoners party together.

I don't need a drink, I just smoked a joint, I'm parallel partying with you guys.

parallel partying by 6deluca6 August 30, 2016

Parallel killer 

Someone who kills many people at once

Dave realized that being a parallel killer was much more efficient than being a serial killer.

Parallel killer by Low Bo February 14, 2015

parallel swizzle 

A majestic turn on roller skates performed by rocking the Circle Pad in the opposite direction.

Wow, when he performed that parallel swizzle, he looked like a fucking fairy.

parallel swizzle by intellectualbadass October 21, 2013

parallel partying 

When drinkers and stoners party together.

I am partying, I just smoked a joint, I'm parallel partying.

parallel partying by 6deluca6 August 30, 2016

parallelogram 

any quadrilateral, such as a square, rectangle or rhombus, with opposing parallel sides being of equal length

Usage: Words such as parallelogram, square, rectangle, rhombus, parallel, equal and length, all well-defined in any proper dictionary, are, as Urban Dictionary entries, misplaced and of minimal benefit.

parallelogram by Scott Fairbairn October 18, 2008