Backflow is a phenomenon that occurs when the normal flow of water is reversed. It is caused by a pressure difference between two points, which can be caused by a variety of factors such as changes in elevation, wind, or temperature. The term 'backflow' is often used to describe the reversal of the flow of water in a river or stream. The crossword solutions for the term backflow are EBB (3 letters) and EDDY (4 letters). EBB is a term used to describe the outward flow of water from the shoreline, while EDDY is a term used to describe a circular current of water that flows in the opposite direction of the main current.