Definition of diffuse in US English:



Pronunciation /dəˈfjuz//dəˈfyo͞oz/
  • 1Spread or cause to spread over a wide area or among a large number of people.

    no object ‘technologies diffuse rapidly’
    with object ‘the problem is how to diffuse power without creating anarchy’
    • ‘Once a musical form is created, it diffuses geographically and culturally.’
    • ‘People, ideas, and capital are less mobile so that technology diffuses more slowly than in the other scenario families.’
    • ‘It works efficiently to create and diffuse purchasing power throughout the economy and disseminate liquidity throughout the financial system.’
    • ‘The ink will be visibly distinguishable from the water for some amount of time, but it will diffuse eventually to all areas of the beaker.’
    • ‘Otherwise, this staging, full of padding and smart-aleck references, diffuses Wagner's musical power: it is an elemental drama gelded by unasked questions and a lack of ambition.’
    • ‘His heart sank, fear spread and diffused through his body.’
    • ‘The rule of law dilutes power; it diffuses it; and yet it also makes it more efficient.’
    • ‘Perfecting this technology would not only diffuse a contentious ethical and political issue, it is also the ideal solution from a scientific perspective.’
    • ‘Power, especially economic power, has been diffused.’
    • ‘It diffuses competition and gradually creates a co-operative dynamic where people can feel safe to air their concerns.’
    • ‘Knowledge and power are both diffused downward throughout the system.’
    • ‘Technology today is diffusing faster than ever.’
    • ‘But slowly, in the course of time the proletarian agenda of the communist parties is also diffusing rapidly.’
    • ‘It diffuses and redistributes power, often to the benefit of what may be considered weaker, smaller actors.’
    • ‘The Second World War produced the weapons which characterized all post-war conflicts, and diffused this technology world-wide.’
    • ‘This is indigenous to Brazil, where it is known as aroreira, but since the 19th century has been widely diffused in other tropical areas.’
    • ‘The technology can be expected to diffuse rapidly as all major vendors are developing such systems and many are pursuing internet based applications which would allow ordering and provide a common platform.’
    • ‘It has diffused a wider lack of confidence on the part of investors and consumers, accentuating the trend towards recession.’
    • ‘They were under-represented in the gold and other mining regions, and were diffused widely in rural areas.’
    • ‘We must understand that Western technology diffuses to the rest of the world by moving sidewise, not disruptively.’
    spread, spread out, spread around, send out, scatter, disperse
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    1. 1.1Physics Become or cause (a fluid, gas, individual atom, etc.) to become intermingled with a substance by movement, typically in a specified direction or at specified speed.
      no object ‘oxygen molecules diffuse across the membrane’
      with object ‘gas is diffused into the bladder’
      • ‘It is initially absorbed into the fat layers under the skin, then is diffused into the capillaries where it enters the blood stream as needed.’
      • ‘The interior of channel-forming membrane proteins contains a column of water molecules through which protons and other small ions can diffuse across the membrane.’
      • ‘Unfortunately, the majority of cancer deaths are due to metastases from malignant cells that have stealthily diffused into adjacent tissues and into organs far from the primary.’
      • ‘During such movement, oil molecules diffused into the cytoplasm of both palisade and spongy cells.’
      • ‘During this unwinding period the alkali diffused into the viscous lysate to give a final pH of 12.4.’
    2. 1.2with object Cause (light) to glow faintly by dispersing it in many directions.
      • ‘The fourth side is screened by lightweight wattle wall that gently diffuses the harsh light.’
      • ‘The incandescent bulbs, silvered on the tops to diffuse their light in a soft spread over the wall, function as punctuation points and visual anchors.’
      • ‘It's refreshing these days to be reminded how good film can be when film-makers don't plane every rough edge and diffuse each harsh ray of sun, like make-over artists gone berserk.’
      • ‘The spatial sequence is crowned by the parallel skylight bars which diffuse a soft luminance into the gallery spaces.’
      • ‘For this one, I put two cheap tungsten spots on the other side of the door, and taped white tissue paper all along the opening to diffuse the light.’
      • ‘Slatted or lattice style roofs are just enough to diffuse the sun's rays when they are at their peak without covering your deck or patio completely.’
      • ‘This background serves to diffuse the light and alters as the light itself changes and moves, creating a shimmering effect.’
      • ‘They need at least six hours a day of indirect sunlight; if direct sun can't be avoided, diffuse the light with a shade or sheer curtain.’
      • ‘The lights were diffused, casting a soft peach-shaded glow over everything.’
      • ‘The tape doesn't reduce light transmission too much but serves to diffuse the direct rays that get by the shields.’
      • ‘Lighter window treatments such as voile and muslin can diffuse daylight into a room with designer effects.’
      • ‘As the day progresses, the weather starts to take on a gloomy appearance, with dark, gray clouds moving in, covering up the sky and diffusing the sunlight.’
      • ‘Upstairs, etched glass light wells diffuse luminance into the restaurant and glazed screens enclose private rooms.’
      • ‘And in the double-height exhibition space, two large window-screens, with built-in shutters, serve to break up and diffuse the sunlight.’
      • ‘This causes light to be reflected evenly rather than being diffused by empty pores, creating a shinier surface.’
      • ‘Incorporated within the timber louvres are troughs for planting that will gradually become established on the north side, screening and diffusing the sun's glare.’
      • ‘This is accomplished by either bouncing the light off a surface before it reaches your subject or by moving the flash off the camera and diffusing the light.’
      • ‘Fretted screens diffuse the light, and wooden doors and panels are delicately carved.’
      • ‘The morning light was diffused to a mucky orange by the pollution of the shuddering city.’
      • ‘Using wood for its easy working but not liking its ‘natural wood’ look, the final touch would be an integral black paint which let the acrylic inserts diffuse the blue light through it.’
      spread, spread out, spread around, send out, scatter, disperse
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Pronunciation /dəˈfjus//dəˈfyo͞os/
  • 1Spread out over a large area; not concentrated.

    ‘the diffuse community centered on the church’
    ‘the light is more diffuse’
    • ‘We are interested in ideas, stories and voices that are overlooked by the dominant media, and in contributing to a more diverse and diffuse public culture.’
    • ‘In addition, stock ownership became more diffuse, enabling middle-class Americans to benefit from economic growth.’
    • ‘If the state spreads itself too thinly across the disconnected and diffuse networks of personal identity, it will simply dissipate.’
    • ‘First, it moves a great deal of diffuse wealth and concentrates it in the hands of the war industry.’
    • ‘Instead it comes from several diffuse sources spread over a large geographical area.’
    • ‘Everywhere people are promenading, basking in the miraculous light: warm, long, slanting, at once brilliant and diffuse.’
    • ‘When, on the other hand, the target group is large and diffuse, as it is for women, it is more difficult to direct resources and tailor programs towards that group.’
    • ‘Work-based networks, diffuse friendships and shared or mutually acknowledged social values are also forms of social capital.’
    • ‘And people on the streets outside the immediate blast zone would be exposed to a very small dose of dissipating radiation, made even more diffuse by the explosion itself.’
    • ‘The new threats were going to be diffuse, spread out, springing up wholly formed from unexpected quarters.’
    • ‘The loss they see is personal and immediate, while the benefits of increased productivity, competitiveness and innovation are diffuse and global.’
    • ‘American games quickly united a diffuse immigrant community struggling for ways to become more American.’
    • ‘Church officials were appointed on a regional basis so as to bind a diffuse community.’
    • ‘The label's glowing globalism and diffuse spirituality are still intact, and they're no strangers to neo-dub with a world-beat bent, which is the theme on their latest comp.’
    • ‘Older people, an important category of newspaper readers, are also exhibiting more diffuse community ties.’
    • ‘At the national level, however, this kind of more direct control is more difficult to achieve given the complex and diffuse nature of patronage networks.’
    • ‘Prose is discursive, its energies more diffuse and spread out across space and time.’
    • ‘Its large ecological potential and diffuse dispersal contribute significantly to the mosaic structure of many meadow communities.’
    • ‘I find this area diffuse with a billion reasons advanced for becoming serious or evasive over serious music.’
    • ‘By the time of the Civil War, a black fiddle tradition, which still exists in some regions of the Southeast today, was diffuse through that area.’
    spread out, diffused, scattered, dispersed, not concentrated
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    1. 1.1 (of disease) not localized in the body.
      ‘diffuse hyperplasia’
      • ‘The majority of these patients were initially suspected of having an infectious etiology for their diffuse pulmonary disease.’
      • ‘The diagnoses, therefore, were hyperreactive airway disease and diffuse intrapulmonary telangiectasia.’
      • ‘Condylomata represent a focal manifestation of a diffuse infection and occur in only a minority of those infected with HPV.’
      • ‘In general, signs of focal or diffuse inflammation superior to the spinal cord were mild.’
      • ‘Bronchocentric granulomatosis can present radiologically as a single mass, as multiple masses, or as a more diffuse disease.’
    2. 1.2 Lacking clarity or conciseness.
      ‘the second argument is more diffuse’
      • ‘What I am basically saying is there are so many different strands of accountability in one way or another, the whole context of accountability can get somewhat diffuse; would you share that view?’
      • ‘Without the emotional drive that the US brought to bear on a quite unprecedented situation, the international community's response is likely to have been confused and diffuse.’
      • ‘But it might as well be scrapped if it becomes too accommodating and diffuse to remain meaningful.’
      • ‘Although such a study clearly runs the risk of feeling diffuse and disconnected, her work succeeds because she uses a similar heuristic with each war and each text.’
      • ‘His third volume is his most diffuse work.’
      • ‘And for my money Ryan's use of viewpoint is too diffuse.’
      • ‘The large painting is strangely diffuse and lacking in structure for that master of tight, well-ordered composition.’
      • ‘His choice of difficult and often diffuse texts, with which most students of of the classics have but a passing acquaintance, means that his services are not always recognized.’
      • ‘Defined in parallel with synesthesia as the blending of images or concepts, metaphor enables us to make concrete what is diffuse, familiar what is unfamiliar.’
      • ‘Though filled with powerful, often hilarious moments, it is too diffuse.’
      • ‘Last time, the Biennial was a group curatorial effort, and the result was a rather diffuse exhibition.’
      • ‘Like the Republicans, the protesters here in Philadelphia are mainly staying on message, but their message is very diffuse.’
      • ‘Today, the term has something of a diffuse meaning.’
      • ‘But, unaware as I am that this is my real goal, my dissatisfaction will remain diffuse and unintelligible to me.’
      • ‘She is both the discerning scholar from the West who has managed to keep a sense of perspective and balance in a diffuse narrative and an enchanted participant in the action.’
      • ‘More generally, his writing style is somewhat diffuse, full of jokes and asides, with the result that his line of analysis is sometimes opaque.’
      verbose, wordy, prolix, long-winded, overlong, long-drawn-out, protracted, discursive, rambling, wandering, meandering, maundering, digressive, circuitous, roundabout, circumlocutory, periphrastic
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The verbs diffuse and defuse sound similar but have different meanings. Diffuse means, broadly, ‘disperse,’ while the nonliteral meaning of defuse is ‘reduce the danger or tension in.’ Thus sentences such as Cooper successfully diffused the situation are regarded as incorrect, while Cooper successfully defused the situation would be correct. However, such uses of diffuse are widespread, and can make sense: the image in, for example, only peaceful dialogue between the two countries could diffuse tension is not of making a bomb safe but of reducing something dangerous to particles and dispersing them harmlessly


Late Middle English: from Latin diffus- ‘poured out’, from the verb diffundere, from dis- ‘away’ + fundere ‘pour’; the adjective via French diffus or Latin diffusus ‘extensive’, from diffundere.