Толковый словарь английского языка - diffusion

noun Date: 14th century the action of diffusing ; the state of being diffused, prolixity, diffuseness, 3. the process whereby particles of liquids, gases, or solids intermingle as the result of their spontaneous movement caused by thermal agitation and in dissolved substances move from a region of higher to one of lower concentration, b. reflection of light by a rough reflecting surface, transmission of light through a translucent material ; scattering, the spread of cultural elements from one area or group of people to others by contact, the softening of sharp outlines in a photographic image, ~al adjective