diffusion

noun

dif·​fu·​sion di-ˈfyü-zhən 

1

: the state of being spread out or transmitted especially by contact : the action of diffusing

the diffusion of knowledge

2

: prolixity, diffuseness

3

a

chemistry : the process whereby particles of liquids, gases, or solids intermingle as the result of their spontaneous movement caused by thermal (see thermal entry 1 sense 1b) agitation and in dissolved substances move from a region of higher to one of lower concentration

b physics

(1)

: reflection of light by a rough reflecting surface

(2)

: transmission of light through a translucent material : scattering

4

: the spread of cultural elements from one area or group of people to others by contact

5

photography : the softening of sharp outlines in an image

diffusional

di-ˈfyü-zhə-nᵊl 

adjective

Synonyms

• circumlocution
• diffuseness
• garrulity
• garrulousness
• logorrhea
• long-windedness
• periphrasis
• prolixity
• redundancy
• verbalism
• verbiage
• verboseness
• verbosity
• windiness
• wordage
• wordiness

Examples of diffusion in a Sentence

the author's tendency toward diffusion makes the novel a tedious read

Recent Examples on the Web

At the same time, middle powers trying to avoid coming under the shadow of either superpower, along with tech companies devoted to the global diffusion of technology through open markets, see AI development paving the path to a multipolar world. —Reva Goujon, Foreign Affairs, 27 Dec. 2024

In life sciences, diffusion models have inspired innovations like MIT’s DiffDock, which predicts how drug molecules will bind to proteins—a critical step in designing new therapies. —Harini Gopalakrishnan, Forbes, 20 Dec. 2024

And the diffusion makes the air a bit more gentle on your hair, leaving behind less damage. —Louryn Strampe, WIRED, 11 Dec. 2024

One electrochemical process uses gas diffusion electrodes (GDEs) with a catalyst to convert carbon dioxide gas into ethylene, which can be used as a fuel or as a chemical precursor for plastics and other materials. —IEEE Spectrum, 18 Dec. 2024

Word History

Etymology

Middle English diffusioun "outpouring (of speech)," borrowed from Late Latin diffūsiōn-, diffūsiō "pouring out (of liquids), watering of the eyes, abundance" (Latin, "geniality"), from Latin diffud-, variant stem of diffundere "to pour out over a wide surface, spread out, extend" + -tiōn-, -tiō, suffix of verbal action — more at diffuse entry 2

First Known Use

15th century, in the meaning defined at sense 2

Kids Definition

diffusion

noun

dif·​fu·​sion dif-ˈyü-zhən 

1

: a diffusing or a being diffused

2

: the mixing of particles of liquids, gases, or solids so that they move from a region of high concentration to one of lower concentration

3

: the scattering of light by reflection from a rough surface or by passage through a translucent material (as frosted glass)

Medical Definition

diffusion

noun

dif·​fu·​sion dif-ˈyü-zhən 

1

: the process whereby particles of liquids, gases, or solids intermingle as the result of their spontaneous movement caused by thermal agitation and in dissolved substances move from a region of higher to one of lower concentration

2

a

: reflection of light by a rough reflecting surface

b

: transmission of light through a translucent material

diffusional

-ˈyüzh-nəl, -ən-ᵊl 

adjective