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
  1. noun
    the act of dispersing or diffusing something
    “the diffusion of knowledge”
    synonyms: dispersal, dispersion, dissemination
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    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
  2. noun
    the property of being diffused or dispersed
    synonyms: dissemination
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    type of:
    dispersion, distribution
    the spatial or geographic property of being scattered about over a range, area, or volume
  3. noun
    the spread of social institutions (and myths and skills) from one society to another
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    type of:
    spread, spreading
    process or result of distributing or extending over a wide expanse of space
  4. noun
    (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)
Word Family

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