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diffusion

noun dif·fu·sion \ di-ˈfyü-zhən \
|Updated on: 3 Aug 2018

Definition of diffusion

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 1thermal 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

play \-ˈfyü-zhə-nᵊl\ adjective

See diffusion defined for kids

Examples of diffusion in a Sentence

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

Recent Examples of diffusion from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diffusion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of diffusion

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 2diffuse

Other Physics Terms

amplitude, centrifugal, centripetal, convection, gradient, hysteresis, kinetic, lase, quantum

DIFFUSION Defined for Kids

diffusion

noun dif·fu·sion \ di-ˈfyü-zhən \

Definition of diffusion for Students

1 : the act of spreading or allowing to spread freely
2 : the mixing of particles of liquids or gases so that they move from a region of high concentration to one of lower concentration

Medical Dictionary

diffusion

noun dif·fu·sion \ dif-ˈyü-zhən \

medical Definition of diffusion

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

play \-ˈyüzh-nəl, -ən-ᵊl\ adjective

Learn More about diffusion

  1. See words that rhyme with diffusion Spanish Central: Translation of diffusion Nglish: Translation of diffusion for Spanish speakers Britannica English: Translation of diffusion for Arabic speakers Britannica.com: Encyclopedia article about diffusion

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