The word quintessential comes from the Latin word quintus, meaning “fifth,” and essentia, meaning “essence” or “being.” In medieval alchemy, it was believed that there were four elements—earth, air, fire, and water—and that a fifth element, known as quintessence, was the substance that made up the heavenly bodies. In English, quintessential has been used since the 16th century to describe something that is the most perfect example of its kind. Today, it is a common word in English, and is often used to describe people or things that are classic, perfect, or ideal.