¹ diamond noun

• a very hard usually colorless stone that is a form of carbon and is used especially in jewelry —often used before another noun
• a shape that is formed by four equal straight lines and that has two opposite angles that are smaller than a right angle and two opposite angles that are larger than a right angle
• a playing card that is marked with a red diamond shape

² diamond adjective

• of or relating to the 60th or 75th anniversary of an important event (such as a marriage)