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 Color patterns emerge depending on the differences in the two proteins' diffusion rates. Elizabeth Pennisi, Science | AAAS, "Meet the monkeyflower, a weed that may hold the key to zebra stripes and other biological mysteries," 29 Aug. 2019 Sustaining the union is in part about striking a balance between diffusion and cohesion. Fred Bauer, National Review, "What the Nationalism vs. Liberalism Debate Misses," 28 Aug. 2019 Heat diffusion and Brownian motion are just two examples. Quanta Magazine, "The Puzzling Search for Perfect Randomness," 20 Aug. 2019 How cells make sense of these diffusion gradients has always been a mystery. Jordana Cepelewicz, WIRED, "The Mysterious Math of How Cells Determine Their Own Fate," 24 Mar. 2019 Turing predicted that some patterns emerge from the natural diffusion and interactions of proteins whose concentrations regulate each other's production. Elizabeth Pennisi, Science | AAAS, "Meet the monkeyflower, a weed that may hold the key to zebra stripes and other biological mysteries," 29 Aug. 2019 Many observers, in fact, see the diffusion of power within Maduro’s government as the single biggest barrier to a deal. Washington Post, "During secret Venezuela talks, Maduro offered new elections. Is it a real breakthrough or a stall?," 18 Aug. 2019 Reporters do not understand the subtle diffusion of decision-making power within the Federal Reserve. Edward Lotterman, Twin Cities, "Edward Lotterman: Hooray for complexity in the Federal Reserve’s structure," 3 Aug. 2019 The second was Diffusion Tensor Imaging (DTI), which uses the diffusion of water molecules in brain tissue to glean information about tissue integrity and microstructures. Beth Mole, Ars Technica, "Brain imaging weirdness adds to Cuba “health attack” mystery," 24 July 2019

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

12 Oct 2019

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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