Tetragons are four-sided polygons that can also be referred to as quadrilaterals. Other synonyms for tetragons include rectangles, squares, trapezoids, rhombuses, and parallelograms depending on their specific characteristics. Rectangles have four right angles and opposite sides that are equal in length, while squares have all sides the same length. Trapezoids have at least one pair of parallel sides, and their opposite sides are of unequal length. Rhombuses have four equal sides, while parallelograms have opposite sides that are equal and parallel. Understanding the different types of tetragons and their synonyms can help when working with geometry and mathematical formulas.