diffusion in WordNet English dictionary

1. the act of dispersing or diffusing something
   "the dispersion of the troops"; "the diffusion of knowledge"
   dispersion  dispersal  dissemination  diffusion 
   
2. the property of being diffused or dispersed
   dissemination  diffusion 
   
3. the spread of social institutions (and myths and skills) from one society to another
   diffusion 
   
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
   diffusion