Diffusion is the act of dispersing something, spreading it out from a central point. When an idea catches on, that's a type of diffusion.

When you spray air freshener and the scent spreads from a tight space to fill a larger one, that's diffusion. In science, diffusion is a physical process of atoms or molecules moving apart within a gas or liquid. You can also use the word diffusion to describe the spreading of information. Ever notice how a trendy word or band will suddenly be everywhere, even though nobody heard of it last week? That's diffusion. This word means something similar to dispersal and dissemination.

Definitions of diffusion

n the act of dispersing or diffusing something

“the diffusion of knowledge”
dispersal, dispersion, dissemination
crop-dusting, spraying
the dispersion of fungicides or insecticides or fertilizer on growing crops (often from a low-flying aircraft)
Type of:
spread, spreading
act of extending over a wider scope or expanse of space or time

n the property of being diffused or dispersed

Type of:
dispersion, distribution
the spatial or geographic property of being scattered about over a range, area, or volume

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

Type of:
spread, spreading
process or result of distributing or extending over a wide expanse of space

n (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

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(biology, chemistry) diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration until the concentration on both sides is equal
permeation, pervasion, suffusion
the process of permeating or infusing something with a substance
an exchange of molecules (and their kinetic energy and momentum) across the boundary between adjacent layers of a fluid or across cell membranes
active transport
transport of a substance (as a protein or drug) across a cell membrane against the concentration gradient; requires an expenditure of energy
impregnation with ammonia or a compound of ammonia
saturation with carbon dioxide (as soda water)
impregnation, saturation
the process of totally saturating something with a substance
reverse osmosis
(chemistry) a method of producing pure water; a solvent passes through a semipermeable membrane in a direction opposite to that for natural osmosis when it is subjected to a hydrostatic pressure greater than the osmotic pressure
passive transport
transport of a substance across a cell membrane by diffusion; expenditure of energy is not required
Type of:
action, activity, natural action, natural process
a process existing in or produced by nature (rather than by the intent of human beings)

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