Name a polygon with 4 sides, none of which are the same size?
An irregular quadrilateral.
Quadrilaterals are polygons with four sides (hence the beginning "quad", which means "four").
A polygon with non-equal sides is called irregular, so the figure that you are describing is an irregular quadrilateral.
This figure has side lengths of 1, 2, 3, and 4 respectively, so it is an irregular quadrilateral.