Substances moving down a concentration gradient passively.
The best example of cultural diffusion would be when the Europeans interacted with the Americans. They both taught each other about their cultures.
The best recipe for baked ham would be very simple, it would bring out the flavor of the ham while still contributing variety, and it would yield a delicious and crowd-pleasing result.
An essay to describe your best friend would include the best traits of the best friend. The essay would also describe why you feel those traits are beneficial to your friendship.
Beautiful
simple-hearted, caring, loving, supportive, gentle
scientific
Zenith
relaxed
Zenith
anything that have some of your best work
Diffusion is the process of spreading something more widely. It can be the diffusion of Homo Sapiens from the plains of Africa, the diffusion of a drop of ink in a bucket of water, diffusion of the use of smart phones.
Hellion would describe Hindley.