Rhombi, alternatively known as rhombuses, are quadrilaterals with four sides of equal length. They are often seen in diamonds and playing cards. Some synonyms for rhombi include lozenges, diamonds, and rhombs. Lozenges are used in medicine as medicated tablets or candies. Diamonds are precious gemstones, often used in jewelry. Rhombs can also refer to parallelograms with acute or obtuse angles. Other synonyms for rhombi include quadrilaterals, squares, rectangles, and parallelograms. Quadrilaterals are four-sided polygons while squares are equilateral rectangles. Rectangles have four right angles and parallelograms have opposite sides parallel and congruent. All these shapes are similar to rhombi in one way or another.