Dispersion is a process by which (in the case of solid dispersing in a liquid) agglomerated particles are separated from each other, and a new interface between the inner surface of the  liquid dispersion medium and the surface of the dispersed particles is generated. This process is facilitated by molecular diffusion and convection.
With respect to molecular diffusion, dispersion occurs as a result of an unequal concentration of the introduced material throughout the bulk medium. When the dispersed material is first introduced into the bulk medium, the region at which it is introduced then has a higher concentration of that material than any other point in the bulk. This unequal distribution results in a concentration gradient that drives the dispersion of particles in the medium so that the concentration is constant across the entire bulk. With respect to convection, variations in velocity between flow paths in the bulk facilitate the distribution of the dispersed material into the medium.
Although both transport phenomena contribute to the dispersion of a material into the bulk, the mechanism of dispersion is primarily driven by convection in cases where there is significant turbulent flow in the bulk. Diffusion is the dominant mechanism in the process of dispersion in cases of little to no turbulence in the bulk, where molecular diffusion is able to facilitate dispersion over a long period of time. These phenomena are reflected in common real-world events. The molecules in a drop of food coloring added to water will eventually disperse throughout the entire medium, where the effects of molecular diffusion are more evident. However, stirring the mixture with a spoon will create turbulent flows in the water that accelerate the process of dispersion through convection-dominated dispersion.