diffúzió

In physics and chemistry, the passive movement of particles, such as atoms or molecules, from a region of higher concentration to a region of lower concentration as a result of random thermal motion.

In biology, the passive movement of molecules, such as gases or small solutes, across cell membranes from an area of higher concentration to an area of lower concentration without the use of cellular energy.

The slow and widespread spreading of something, such as ideas, practices, products, or information, through a population or across a region.