Q. What is a round cushion called?

Answer

A round cushion is called a bolster pillow. Whether it's made of cotton, down, or fiber, a bolster is a long, narrow pillow or cushion. A bolster's many purposes including serving as a decorative element, providing support for the back or arms, and more. They can be found in a wide range of sizes and forms and often include a zipper or hook-and-loop closure. A foam insert is commonly used to provide additional comfort. Middle English borrowed it from Old English, where it was a form of the word for "bag," belg. The word "bolster" was likely first used before to the 12th century. Among the Japanese, bolsters are known as dakimakura.