The term 'FREE OF BUMPS' can be summarized by the crossword solution 'SMOOTH, ' which is a six-letter word. SMOOTH is an adjective that describes something that has no bumps, ridges, or other irregularities on its surface. It is often used to describe surfaces that are pleasant to the touch, such as a baby's skin or a polished stone. SMOOTH can also be used to describe a situation that is free of problems or difficulties.