Definition of effusion in English:

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Pronunciation: /əˈfyo͞oZHən/


1An instance of giving off something such as a liquid, light, or smell: a massive effusion of poisonous gas
More example sentences
  • 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.
1.1 Medicine An escape of fluid into a body cavity.
Example sentences
  • 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.
1.2An act of talking or writing in an unrestrained or heartfelt way: literary effusions
More example sentences
  • 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.
outburst, outpouring, gushing, rhapsody;
wordiness, verbiage


Late Middle English: from Latin effusio(n-), from effundere 'pour out' (see effuse).

Words that rhyme with effusion

allusion, collusion, conclusion, confusion, contusion, delusion, diffusion, exclusion, extrusion, fusion, illusion, inclusion, interfusion, intrusion, obtrusion, occlusion, preclusion, profusion, prolusion, protrusion, reclusion, seclusion, suffusion, transfusion

For editors and proofreaders

Syllabification: ef·fu·sion

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