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

The first symptoms are diffuse yellow areas on the top side of leaves, with the plants taking on an overall sick look, and brown spots as the disease progresses. Tim Johnson, chicagotribune.com, "Yellowing basil leaves could mean downy mildew," 26 Aug. 2019 Van Dokkum thinks astronomy’s transition from photographic plates — which were perhaps better suited to picking up extended, diffuse objects — to modern digital sensors may actually have hid them from further attention. Quanta Magazine, "Strange Dark Galaxy Puzzles Astrophysicists," 27 Sep. 2016 On the front line Though the protests remain diffuse, without a visible leader, a few young activists have stepped to the forefront of some actions. Suzanne Sataline, The Christian Science Monitor, "Hong Kong protests: Is anyone in charge?," 9 July 2019 The event technically begins at 2:44 p.m. ET (18:44 UT) with a penumbral eclipse, when Earth’s more diffuse outer shadow, or penumbra, falls across the moon. Andrew Fazekas, National Geographic, "See a lunar eclipse on the Apollo 11 launch anniversary," 16 July 2019 Though rendered saltily by Wingert, Joyce is a diffuse character … a collection of attitudes and opinions unmoored from underlying motivation. Dominic P. Papatola, Twin Cities, "Review: ‘Stinkers’ has some sweet moments, but has some growing-up to do," 20 July 2019 In most experiments, researchers awaken opsin-bearing neurons of a specific cell type with a pulse of diffuse blue-green light. Kelly Servick, Science | AAAS, "Laser holograms stimulate brain cells in mice to probe roots of perception and hallucination," 18 July 2019 Employees at other big tech firms had helped created a playbook that turns diffuse pockets of dissent into an organized force that reaches the executive offices or the public in a hurry — and that is easily copied. Globe Staff, BostonGlobe.com, "Wayfair walkout is part of a new era of employee activism," 29 June 2019 Nature has innate mystery; its smallest building blocks simply are fuzzy and diffuse objects. Sophia Chen, WIRED, "Physicists Hack the Uncertainty Principle to See an Ion Wiggle," 20 June 2019

Recent Examples on the Web: Verb

It is disposed of by returning it to the ocean and—if not done properly by diffusing it over large areas—can deplete the ocean of oxygen and have negative impacts on sea life. Jim Robbins, WIRED, "Desalination Is Booming as Cities Run out of Water," 27 June 2019 Compromise is the only way to diffuse a tense situation. Tribune Content Agency, oregonlive.com, "Horoscope for June 15, 2019: Happy birthday to actress Helen Hunt; Cancer, you can always change your mind," 15 June 2019 Communities surrounding artists and their work can often appear diffused online, particularly as forums have given way to broader social media platforms. Lewis Gordon, The Verge, "Patreon has become a lifeline for creators of weird, alternative games," 14 Aug. 2019 Two proteins that exclude each other activate on the cell membrane at opposite ends of the cell, so that where one is present, the other can’t diffuse. Quanta Magazine, "For Embryo’s Cells, Size Can Determine Fate," 12 Aug. 2019 Is doing so essential somehow for society’s psychological well-being, an attempt to collectivize experience increasingly diffused by the distractions of the internet? Alyson Krueger, New York Times, "It’s the Anniversary of Everything!," 2 Aug. 2019 At eye-level, Maxwell’s shadow was slightly escapist in nature, the warming tone diffusing toward the brow, while the model’s painted matte lip was further defined by a visible delineation of lip liner. Calin Van Paris, Vogue, "Stella Maxwell Puts a Twist on the Makeup Hue of the Moment," 12 July 2019 If using peppermint oil to deter skunks, the oil should be applied to cotton balls and placed in containers that will allow the smell to diffuse but prevents actual contact with it by your pets. Joan Morris, The Mercury News, "Seemingly benign skunk deterrent can be dangerous for cats," 14 June 2019 The police chief recognized those in the community who attempted to diffuse the situation. NBC News, "Dozens of officers injured during protest in Memphis after task force kills man," 13 June 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

Statistics for diffuse

Last Updated

24 Sep 2019

Look-up Popularity

Time Traveler for diffuse

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

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More Definitions for diffuse

diffuse

adjective

English Language Learners Definition of diffuse

 (Entry 1 of 2)

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

diffuse

verb

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

Rhyming Dictionary: Words that rhyme with diffuse

Thesaurus: All synonyms and antonyms for 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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to wander slowly or to speak indistinctly

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