Rhombus
Rectangle
Parallelogram
A square.
A parallelogram has 2 pairs of parallel sides, and provided that it isn't a square, it has no square corners. If necessary, you could call it an "oblique parallelogram" to indicate that it isn't square.
quadrilateral quadrangle
A trapezium (trapezoid) has only one pair of parallel sides, a parallelogram has two pairs.
It is a shape that consists of at least four sides that's why they call it a QUADrangle
A quadrilateral is a polygon with 4 sides. ... Definition: A parallelogram is a quadrilateral where both pairs of opposite sides are parallel. We use the symbol to represent a 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.A simple (non self-intersecting) quadrilateral is a parallelogram if and only if any one of the following statements is true;Two pairs of opposite sides are equal in lengthOne pair of opposite sides are parallel and equal in length.source:From Wikipedia, the free encyclopedia;Subject: Parallelogram.
None of that is true of a rhombus. -- A rhombus must have two pairs of parallel sides. -- A rhombus need not have any square corners. But if it has any at all, then it has four of them, and most people looking at it would call it a square.
Quadrilaterals usually have special names only if they DO have parallel sides, or some other special property. You might just call it "quadrilateral", or "a quadrilateral with no parallel sides".