From Wikipedia, the free encyclopedia.
In geometry, a rhombus is a quadrilateral in which all of the sides are of equal length. Opposite sides are parallel.
The rhombus is a special case of the parallelogram, in that all sides are equal: the rhombus is to the parallelogram what the square is to the rectangle.
If all the angles are right angles, it is then a square.
The only plane figure that is both a rhombus and a rectangle is a square.
