A waist cincher is an item of clothing that is used to cinch the waist and create a more defined silhouette. It is also known as a SASH, which is a four-letter word that can be used to solve the crossword. Waist cinchers are usually made of fabric and are worn around the waist to create a slimming effect. They are often used in combination with other clothing items such as dresses or skirts to create a more flattering look.