diffusion

noun
dif·​fu·​sion | \ di-ˈfyü-zhən How to pronounce diffusion (audio) \

Definition of diffusion

1 : the state of being spread out or transmitted especially by contact : the action of diffusing the diffusion of knowledge
3a 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

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Other Words from diffusion

diffusional \ di-​ˈfyü-​zhə-​nᵊl How to pronounce diffusional (audio) \ adjective

Examples of diffusion in a Sentence

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

Recent Examples on the Web

Bill Browder, who runs an investment fund that had once operated in Moscow, says Russia used the diffusion system against him, which led to his brief arrest in Spain earlier this year. Angela Charlton, The Seattle Times, "Interpol’s flaws exposed in US-Russia fight over presidency," 21 Nov. 2018 After successful experiments with arugula and wheat cells, Berkeley researchers are now testing nanotube diffusion in tobacco, cotton, and other varieties of wheat. Jill Kiedaisch, Popular Mechanics, "An Advance in Bioengineering Could Pave the Way for Tomorrow’s Superplants," 12 Mar. 2019 One of the earliest and most primitive enrichment techniques used in this endeavor was gaseous diffusion. Umair Irfan, Vox, "Uranium enrichment will be a key point in talks with North Korea. Here’s what it is.," 11 June 2018 The diffusion of medical innovations—which also often originated in Europe—contributed to population explosions in the rest of the world. Walter Russell Mead, WSJ, "Incredible Shrinking Europe," 11 Feb. 2019 And Chuck Close—wow!—needed 16 dye diffusion transfer prints in four rows of four to create one huge (107 9/16-by-86 1/4-inch) not very interesting picture of his now well-known face (1989). William Meyers, WSJ, "‘Eye to I: Self-Portraits From 1900 to Today’ Review: How Artists See Themselves," 19 Nov. 2018 Michael Kors Holdings acquired Jimmy Choo last year, setting itself apart from other fashion conglomerates that tend to grow in scale and revenue strictly via licenses, diffusion lines, and the acquisition of more mass-market labels. Carrie Goldberg, Harper's BAZAAR, "Versace Is Not Becoming Michael Kors—the Same Way Jimmy Choo Didn't Become Michael Kors," 26 Sep. 2018 Homes are refuges from sun and heat, built with special features to promote airflow and encourage light diffusion. Liz Stinson, Curbed, "Garden-filled house keeps cool with sandstone," 25 Sep. 2018 One end of the capsule contains a gas-permeable membrane that allows for fast diffusion of gut gases. Beth Mole, Ars Technica, "With ingestible pill, you can track fart development in real time on your phone," 9 Jan. 2018

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.

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First Known Use of diffusion

15th century, in the meaning defined at sense 2

History and Etymology for 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 diffuse entry 2

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Statistics for diffusion

Last Updated

27 Apr 2019

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Time Traveler for diffusion

The first known use of diffusion was in the 15th century

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More Definitions for diffusion

diffusion

noun
dif·​fu·​sion | \ di-ˈfyü-zhən How to pronounce diffusion (audio) \

Kids Definition of diffusion

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

diffusion

noun
dif·​fu·​sion | \ dif-ˈyü-zhən How to pronounce diffusion (audio) \

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
2a : reflection of light by a rough reflecting surface
b : transmission of light through a translucent material

Other Words from diffusion

diffusional \ -​ˈyüzh-​nəl, -​ən-​ᵊl How to pronounce diffusional (audio) \ adjective

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Comments on diffusion

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