Definition of effusion in English:



  • 1An instance of giving off something such as a liquid or gas.

    ‘a massive effusion of poisonous gas’
    mass noun ‘he studied the rates of effusion of gases’
    • ‘To compare the rate of effusion of two different gases such as methane and sulfur dioxide you must first calculate the molar mass of each gas.’
    • ‘The law governing the rates of effusion of two gases is called Graham's law.’
    • ‘Flood basalt eruptions involve the effusion of gigantic volumes of low-viscosity lava that spread out over huge areas.’
    • ‘The sulphur and other effusions caused acid rain, but would have bled from the atmosphere quite quickly.’
    • ‘Less than a month to the elections, and ahead lies a bombardment of mind-numbing party political messages to rival the deadly effusions of a Death Star.’
    outflow, outpouring, outflowing, outrush, rush, current, flood, deluge, emission, discharge, issue
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    1. 1.1Medicine An escape of fluid into a body cavity.
      ‘middle ear effusions’
      • ‘His chest radiograph showed a large globular heart, and an echocardiogram confirmed a pericardial effusion from which two litres of fluid were drained.’
      • ‘Chest radiography confirmed bilateral pleural effusions, and her heart was normal size.’
      • ‘An ultrasound scan showed an effusion from which 3 ml of clear, sterile fluid was aspirated.’
      • ‘Her effusions were drained and the fluid again contained abundant mature lymphoid cells.’
      • ‘Ultrasound examination may show an abnormal effusion or abscess in the tendon sheath.’
  • 2An act of talking or writing in an unrestrained or heartfelt way.

    ‘literary effusions’
    • ‘One of the things that I like about the weblog form is that you get a lot of these vivid and heartfelt effusions.’
    • ‘The freshness and fragrance of literature gave way to a stale effusion.’
    • ‘And of course some of these spoken effusions reminded them of traditional tunes to fit the new words, and the first truly Australian traditional songs were begun and flourished.’
    • ‘By a rather strained extension of the word literature, the police attack on his effusions constitutes an attack on literary freedom, which no one can view with equanimity.’
    • ‘It touched off furrowed-brow effusions on ‘heightened craziness about admissions decisions’ and ‘frantic’ competitiveness.’
    • ‘Ten thousand bouquets, liberally admixed with teddy bears and poetic effusions, were laid around the church, often by people who had come hundreds of miles.’
    • ‘These traits of spoken language belong to a vulgar household, filled with the clamour of a large family fond of coarse jokes and prone to sentimental effusions.’
    • ‘We fear the extreme emotional effusions that would be induced by a victory in Euro 2004 or the 2006 World Cup’.’
    • ‘It seems appropriate to post that here as I picked up the book after reading Ed's many effusions on the topic of all things Marquand.’
    • ‘It is the courage of such women, as well as the challenge of their work, that is made invisible by the pious effusions of any one of us who opts to remain in this country a mere mistress of spices.’
    • ‘The President, who arrives at Gleneagles on Wednesday, will be too cocooned to notice any protests, and is unlikely to be moved by effusions from campaigners.’
    • ‘In private, with his girlfriend, he behaved decorously, and kept his effusions for his dog.’
    • ‘He ignored me, but greeted my companion by name and with a certain effusion.’
    outburst, outpouring, gush, stream of words, flow of speech
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Late Middle English from Latin effusio(n-), from effundere ‘pour out’ (see effuse).