The term 'COLORFUL CIRCLE' can be solved by the word 'AREOLA', which is a 6 letter word. An areola is a small circular area of skin surrounding the nipple on the breast of a female mammal. It is typically darker than the surrounding skin and is often visible through clothing. Areolas can also be found around the eyes, nose, and mouth of some animals. In humans, the color of the areola can vary from pink to dark brown.