diffusion

noun

1. 1

   the act of dispersing or diffusing something

   the dispersion of the troops

   the diffusion of knowledge

2. 2

   the property of being diffused or dispersed

3. 3

   the spread of social institutions (and myths and skills) from one society to another

4. 4

   (physics) the process in which there is movement of a substance from an area of high concentration of that substance to an area of lower concentration