Wiktionary
diffusiophoresis
n. The movement of particles in a fluid caused by diffusion of the fluid
Wikipedia
Diffusiophoresis
Diffusiophoresis is a spontaneous motion of dispersed particles in a fluid induced by a diffusion gradient (also called concentration gradient) of molecular substances that are dissolved in the fluid. This gradient affects structure of the particles in an interfacial double layer and causes sliding motion of the fluid relative to the particle surface.