Dictionary

diffusion en · NOUN

Pronunciation

• (Southern-England) audio
• /dɪˈfju.ʒən/ (General-American)
• /dɪˈfjuː.ʒən/ (Received-Pronunciation)

Etymology

Borrowed from Latin diffūsiō, from diffundō; can be decomposed as diffuse + -ion.

Meanings

1. (countable, uncountable) The act of diffusing or dispersing something, or the property of being diffused or dispersed; dispersion.
2. (countable, uncountable) The scattering of light by reflection from a rough surface, or by passage through a translucent medium.
3. (countable, uncountable) The intermingling of the molecules of a fluid due to random thermal agitation.
   • gaseous diffusion
4. (countable, uncountable) The spread of cultural or linguistic practices, or social institutions, in one or more communities.
   • Even the false-necked vase, though it reaches its widest diffusion at this epoch, is, as we have seen, a type found existing in much earlier strata. 1907, Ronald M. Burrows, The Discoveries In Crete, page 99:
5. (countable, uncountable) The gradual spread and adoption of goods or services.
   • The chief salesman of the A.I. boom, Sam Altman of OpenAI, said there was more resistance to “the diffusion, the absorption” of A.I. into the culture and economy than he expected. 2026 February 21, David Streitfeld, quoting Sam Altman, “People Loved the Dot-Com Boom. The A.I. Boom, Not So Much.”, in The New York Times, →ISSN:
6. (countable, uncountable) Exchange of airborne media between regions in space in an apparently random motion of a small scale.
7. (countable, uncountable) The movement of water vapor from regions of high concentration (high water vapor pressure) toward regions of lower concentration.

Forms

Deriveds

hyperdiffusion · thermodiffusion · biodiffusion · pseudodiffusion · diffusion hypoxia · cultural diffusion · microdiffusion · interdiffusion · diffusion-barrier · self-diffusion · diffusionism · rotodiffusion · diffusionist · diffusionless · diffusiophoretic · superdiffusion · prediffusion · autodiffusion · rediffusion · hydrodiffusion · vibrodiffusion · diffusional · error diffusion · photodiffusion · subdiffusion · immunodiffusion · elastodiffusion · electrodiffusion

Relateds

diffuser · diffusity · diffuseness

Translations (31)

ro difuzie (in physics, intermingling of molecules) · ru диффу́зия (in physics, intermingling of molecules) · es difusión (in physics, intermingling of molecules) · ru рассе́ивание (in physics, scattering of light) · tl panunuot (in physics, intermingling of molecules) · sh difuzija (in physics, intermingling of molecules) · tr difüzyon (in physics, intermingling of molecules) · ar اِنْتِشَار (in physics, scattering of light) · bg дифузия (in physics, intermingling of molecules) · ab аилалара (in physics, intermingling of molecules) · hi विसरण (in physics, scattering of light) · id difusi (in physics, intermingling of molecules) · pl rozprzestrzenianie (in physics, scattering of light) · fr diffusion (in physics, scattering of light) · hi विसरण (in physics, intermingling of molecules) · cs difuze (in physics, intermingling of molecules) · pl dyfuzja (in physics, intermingling of molecules) · ja 拡散 (in physics, intermingling of molecules) · fi diffuusio (in physics, intermingling of molecules) · sh дифузија (in physics, intermingling of molecules) · fa انتشار (in physics, scattering of light) · nl diffusie (in physics, intermingling of molecules) · cmn 散射 (in physics, scattering of light) · mi ingotanga (in physics, intermingling of molecules) · ca difusió (in physics, intermingling of molecules) · de Diffusion (in physics, intermingling of molecules) · cy trylediad (in physics, intermingling of molecules) · pt difusão (in physics, intermingling of molecules) · cmn 擴散 /扩散 (in physics, intermingling of molecules) · de Streuung (in physics, scattering of light) · fr diffusion (in physics, intermingling of molecules)