The term 'opposite of outflux' can be answered with the 6-letter word 'INFLOW'. INFLOW is the process of something entering a system, such as water or air entering a body of water or a room. Outflux is the opposite, meaning something leaving a system, such as water or air leaving a body of water or a room. INFLOW and outflux are both important processes in many systems, and understanding the difference between them is essential for understanding how these systems work.