A quadrilateral is a 2D shape that has 4 sides
a parallelogram
Assuming that each vertex is used to connect exactly two sides, all two-dimensional shapes will have the same number of sides as vertices. So a shape with 4 sides will have 4 vertices and a shape with 3 sides will have 3 vertices. Think of a square (4 sides, 4 vertices) and a triangle (3 sides, 3 vertices).
A shape with 4 equal sides is a rhombus. If it also has 4 equal angles, then it is a square.
A shape with three sides is called a triangle.
Any shape that has 4 sides is a quadrilateral
The name of the shape is a quadrilateral.
a square
parallelogram
trapezoid
Trapezium
A quadrilateral shape which has 4 sides
A shape with three or more sides is a polygon. Not sure there is a special name for 4 or more sides.
Square
quadlitural
There is no specific name for such a quadrilateral.
A pyramid.