Definitions for "Diffusing"
Those surfaces and glazing that redistribute some of the incident flux by scattering in all directions.
(1) Softening of detail in a print with a diffusion disk or other light-scattering material. (2) Moderating light so that is softened (diffused), generally either by reflecting it off a material that scatters the light, or by placing a diffusing panel of translucent material between the light source and the subject.
process of softening detail in a print with a diffusion disk or other material that scatters light.
Keywords:  spreading
spreading by diffusion
The natural movement of a substance from an area where there is a high concentration of that substance to where there is a low concentration of the same substance.