diffusion
Pronunciation: /dɪˈfjuːʒ(ə)n/
noun
- the spreading of something more widely: the rapid diffusion of ideas and technology
- the action of spreading the light from a light source evenly to reduce glare and harsh shadows.
- Physics the intermingling of substances by the natural movement of their particles: the rate of diffusion of a gas
- Anthropology the dissemination of elements of culture to another region or people.


Origin:
late Middle English (in the sense 'pouring out, effusion'): from Latin diffusio(n-), from diffundere 'pour out'