diffuse

adjective
dif·​fuse | \ di-ˈfyüs How to pronounce diffuse (audio) \

Definition of diffuse

 (Entry 1 of 2)

1 : being at once verbose and ill-organized a diffuse report from the scene of the earthquake
2 : not concentrated or localized diffuse lighting diffuse sclerosis

diffuse

verb
dif·​fuse | \ di-ˈfyüz How to pronounce diffuse (audio) \
diffused; diffusing

Definition of diffuse (Entry 2 of 2)

transitive verb

1a : to pour out and permit or cause to spread freely a drop of blue dye diffused in a glass of water
b : extend, scatter diffusing their ideas throughout the continent
c : to spread thinly or wastefully a government in which power is diffused
2 physics : to subject to diffusion (see diffusion sense 3) especially : to break up and distribute (incident light) by reflection put up a screen to diffuse the light

intransitive verb

1 : to spread out or become transmitted especially by contact The civilization diffused westward.
2 : to undergo diffusion heat from the radiator diffusing throughout the room

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Other Words from diffuse

Adjective

diffusely adverb
diffuseness noun

Verb

diffusible \ di-​ˈfyü-​zə-​bəl How to pronounce diffusible (audio) \ adjective

Choose the Right Synonym for diffuse

Adjective

wordy, verbose, prolix, diffuse mean using more words than necessary to express thought. wordy may also imply loquaciousness or garrulity. a wordy speech verbose suggests a resulting dullness, obscurity, or lack of incisiveness or precision. the verbose position papers prolix suggests unreasonable and tedious dwelling on details. habitually transformed brief anecdotes into prolix sagas diffuse stresses lack of compactness and pointedness of style. diffuse memoirs that are so many shaggy-dog stories

defuse or diffuse?

Many people find it difficult to remember the difference between defuse and diffuse, and when faced with the need for one of these words simply grab whichever one first comes to mind. But it needn’t be this way: the meanings of these two are quite a bit different, and there is a simple way to differentiate between them. Defuse is formed by adding the prefix de- to the word fuse; you are removing the fuse (either literally or figuratively) when you defuse a situation, much as defanging something entails removing the fangs. Diffuse, when used as a verb, tends to carry meanings such as “spread” or “scatter.” Additionally, diffuse is the only one which may be found used as an adjective.

Examples of diffuse in a Sentence

Adjective The forest was filled with a soft, diffuse light. a diffuse speech that took a great deal of time to make a very small point Verb The heat from the radiator diffuses throughout the room. The heat was diffused throughout the room. The photographer uses a screen to diffuse the light. an area of diffused light
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Recent Examples on the Web: Adjective Are Levi’s efforts too diffuse to add up to real impact? Heather Landy, Quartz at Work, "Who will replace Paul Polman as the face of sustainable capitalism?," 18 Dec. 2019 The first movement may have been somewhat diffuse but the payoff was a revelation of inner voices. Zachary Lewis, cleveland, "Cleveland Orchestra paints vibrant self-portrait through Bach, Brahms, and Ades," 14 Oct. 2019 Carbon emissions, invisible and with a slow, diffuse impact, are of a different order. Washington Post, "The Hydrocarbon Era’s Spectacular End," 7 Aug. 2019 The upgrade process involves a complex coordination game where technology is built and shepherded through a voting process by a diffuse ecosystem of developers. Wired, "These Researchers Are Trying to Build a Better Blockchain," 4 Nov. 2019 Argus II offers a relatively crude form of artificial vision; users see diffuse spots of light called phosphenes. Kelly Servick, Science | AAAS, "New technologies promise sharper artificial vision for blind people," 31 Oct. 2019 All too often, Prokofiev Two comes off as little more than a virtuoso showpiece, a brilliant but diffuse display of solo talent. Zachary Lewis, cleveland, "Cleveland Orchestra thrives with European guests, one of them unexpected," 18 Oct. 2019 The idea of protesting in small, diffuse groups was in part aimed at complicating policing efforts, Tang added. John Leicester, San Diego Union-Tribune, "‘Be water’: Police swoop as Hong Kong protests shift tactics," 13 Oct. 2019 This may be because even the most advanced telescope lenses scatter too much incoming light to pick up the faint mergers of small and diffuse galaxies. Quanta Magazine, "Off-the-Shelf Lens Assists Dark Matter Find," 28 Sep. 2016 Recent Examples on the Web: Verb Those atoms will diffuse through the metal lattice, then combine to form hydrogen gas again on the other side. Eric Hand, Science | AAAS, "Company to harvest green hydrogen from underground oil fires," 6 Feb. 2020 The problem can reach far from big cities: Bright light gets diffused in the atmosphere and can be reflected into the wilderness. Shola Lawal, New York Times, "Fireflies Have a Mating Problem: The Lights Are Always On," 3 Feb. 2020 In an attempt to diffuse crowds and slow the spread of the virus, China has extended the Lunar New Year holiday by up to a week in some places. Aj Willingham, CNN, "5 things to know for January 30: Impeachment, Iraq, coronavirus, 2020 Dems, Tanzania," 30 Jan. 2020 Use the flat end to diffuse the color across your cheeks and up to your temples. Hana Hong, Marie Claire, "I Tried Spring 2019's Coolest Graphic Makeup Looks," 25 Nov. 2019 Enthusiasm helps to diffuse many football differences. SI.com, "Exclusive: Juan Sebastián Veron on the Best Coach He Worked With & Playing With Maradona & Messi," 19 Sep. 2019 The diffuser attaches to the arm of your showerhead and then the pod diffuses the essential oil blend when the water is turned on. Popular Science, "Shower upgrades to enhance make your get-clean routine a bit more luxurious," 5 Sep. 2019 Fog along the Pacific Coast is like a meditation; dampening sounds, softening the edges of objects, diffusing light. Ellen Fort, Sunset Magazine, "The Ultimate Mushroom Trip? A Foraging Weekend in Big Sur," 15 Jan. 2020 Use more product along the cheekbone, then diffuse it up towards the temple, pushing it in and upwards. Jessica Teich, Good Housekeeping, "14 Tips for Applying Blush Perfectly, Every Single Time," 18 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diffuse.' 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 diffuse

Adjective

1612, in the meaning defined at sense 1

Verb

15th century, in the meaning defined at transitive sense 1a

History and Etymology for diffuse

Adjective

Middle English, "dispersed, verbose (of speech or writing)," borrowed from Middle French & Latin; Middle French diffus, borrowed from Latin diffūsus "spread over a wide area, (of writing) extensive, verbose," from past participle of diffundere "to pour out over a wide surface, spread, extend, squander" — more at diffuse entry 2

Verb

Middle English, in past participle diffusid, borrowed from Latin diffūsus, past participle of diffundere "to pour out over a wide surface, spread out, extend, squander," from dif-, assimilated form of dis- dis- + fundere "to pour, shed" — more at found entry 5

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Learn More about diffuse

Time Traveler for diffuse

Time Traveler

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

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Statistics for diffuse

Last Updated

31 Dec 2019

Cite this Entry

“Diffuse.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diffuseness. Accessed 16 Feb. 2020.

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More Definitions for diffuse

diffuse

adjective
How to pronounce diffuse (audio)

English Language Learners Definition of diffuse

 (Entry 1 of 2)

: spread out over a large space : not concentrated in one area

diffuse

verb
How to pronounce diffuse (audio)

English Language Learners Definition of diffuse (Entry 2 of 2)

: to spread out : to move freely throughout a large area
: to exist or be known throughout an area
: to cause (light) to be soft and spread out

diffuse

verb
dif·​fuse | \ di-ˈfyüz How to pronounce diffuse (audio) \
diffused; diffusing

Kids Definition of diffuse

: to spread or allow to spread freely The frosted window diffused the sunlight.

diffuse

adjective
dif·​fuse | \ dif-ˈyüs How to pronounce diffuse (audio) \

Medical Definition of diffuse

 (Entry 1 of 2)

: not concentrated or localized diffuse sclerosis

diffuse

verb
dif·​fuse | \ dif-ˈyüz How to pronounce diffuse (audio) \
diffused; diffusing

Medical Definition of diffuse (Entry 2 of 2)

transitive verb

1 : to subject (as a light beam) to diffusion
2 : to break up and distribute (incident light) by reflection (as from a rough surface)

intransitive verb

: to undergo diffusion

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More from Merriam-Webster on diffuse

Thesaurus: All synonyms and antonyms for diffuse

Rhyming Dictionary: Words that rhyme with diffuse

Spanish Central: Translation of diffuse

Nglish: Translation of diffuse for Spanish Speakers

Britannica English: Translation of diffuse for Arabic Speakers

Comments on diffuse

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