Diffusion - Wikipedia The central idea of diffusion, however, is common to all of these: a substance or collection undergoing diffusion spreads out from a point or location at which there is a higher concentration of that substance or collection
Diffusion | Definition Examples | Britannica Diffusion, process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration A familiar example is the perfume of a flower that quickly permeates the still air of a room