effusion

American  

[ih-fyoo-zhuhn] / ɪˈfyu ʒən /

noun

1. the act of effusing or pouring forth.

2. something that is effused.

3. an unrestrained expression, as of feelings.

   poetic effusions.

4. Pathology.

   1. the escape of a fluid from its natural vessels into a body cavity.

   2. the fluid that escapes.

5. Physics. the flow of a gas through a small orifice at such density that the mean distance between the molecules is large compared with the diameter of the orifice.

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effusion British  

/ ɪˈfjuːʒən /

noun

1. an unrestrained outpouring in speech or words

2. the act or process of being poured out

3. something that is poured out

4. the flow of a gas through a small aperture under pressure, esp when the density is such that the mean distance between molecules is large compared to the diameter of the aperture

5. med

   1. the escape of blood or other fluid into a body cavity or tissue

   2. the fluid that has escaped

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Other Word Forms

• noneffusion
  noun

Etymology

Origin of effusion

1350–1400; Middle English (< Anglo-French ) < Latin effūsiōn- (stem of effūsiō ), equivalent to ef- ef- + fūsion- fusion

Explanation

An effusion is an explosion of something, usually words, ideas, or emotions. A popular singer might inspire an effusion of cheers from her devoted fans. Mozart is known for the effusion of notes he could produce at a moment's notice — and all without erasing. A heated argument can produce an effusion of words from both sides. The volcano's eruption was an effusion of smoke and fire. The verb form of the word is effuse: After the high-school musical, your mother effused about your singing. Her comments were an effusion of praise. Your father, on the other hand, was less effusive — but he did like the dancing.

Example Sentences

Effusion can be defined as the process by which a gas escapes through a pinhole into a vacuum.

From Textbooks • Feb. 14, 2019

Effusion is a similar process in which gaseous species pass from a container to a vacuum through very small orifices.

From Textbooks • Feb. 14, 2019

Effusion is just a fancier word for swelling in the knee.

From Seattle Times • Jun. 8, 2018

His Effusion, and your complaints of his inconstancy, crossed each other on the road.

From The Works of Charles and Mary Lamb — Volume 5 The Letters of Charles and Mary Lamb, 1796-1820 by Lucas, E. V. (Edward Verrall)

Effusion into the knee or ankle, or sometimes both joints, was common in fractures of the shaft of the tibia.

From Surgical Experiences in South Africa, 1899-1900 Being Mainly a Clinical Study of the Nature and Effects of Injuries Produced by Bullets of Small Calibre by Makins, George Henry