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 diffusion (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 Archeologists have tended to explain this development as the result of cultural diffusion: people adopted innovations in pottery, metalworking, and weaponry from their geographic neighbors, along with new burial customs and religious beliefs. Douglas Preston, The New Yorker, "The Skeletons at the Lake," 7 Dec. 2020 The first person in the social diffusion chain told the next person about the articles, the second told the third, and so on. Filippo Menczer, Scientific American, "Information Overload Helps Fake News Spread, and Social Media Knows It," 20 Nov. 2020 Of course, particles emitted during respiration may pass through thin material, but a low pressure drop may aid diffusion, with particles floating around inside the gaiter until they get stuck on fabric or your skin. Joe Lindsey, Outside Online, "What You Need to Know About Wearing a Face Mask Outside," 30 Sep. 2020 Mechanical filters increase in efficiency as particle size gets larger, and due to diffusion and electrostatic attraction, also increase in efficiency as particles get smaller. USA Today, "Ventilation and air filtration play a key role in preventing the spread of COVID-19 indoors," 19 Oct. 2020 The diffusion of fake news is facilitated by the difficulty of a large majority of Americans in distinguishing between fact and opinion. Liv Grjebine, Scientific American, "Why Doubt Is Essential to Science," 9 Oct. 2020 One reason that QAnon is so hard to track is its diffusion across so many online platforms. Gianluca Mezzofiore, Katie Polglase And Tim Lister, CNN, "How a dangerous virtual cult is going global," 7 Oct. 2020 That hasn’t stopped the diffusion of osteopathic ideas into mainstream medicine. Eleanor Cummins, The Atlantic, "Trump’s Doctor Comes From a Uniquely American Brand of Medicine," 6 Oct. 2020 Other things are possible on the space station that simply can't happen on Earth, like cool diffusion flames. Ashley Strickland, CNN, "New toilet, a VR camera and science experiments are launching to the space station," 1 Oct. 2020

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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Time Traveler for diffusion

Time Traveler

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

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Statistics for diffusion

Last Updated

18 Dec 2020

Cite this Entry

“Diffusion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diffusion. Accessed 17 Jan. 2021.

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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 diffusion (audio) \ adjective

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Comments on diffusion

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