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

However, setbacks and pain have persisted, and the effusion, a collection of fluid around the joint also known as water on the knee, have pushed the target back.

From Los Angeles Times • Dec. 3, 2024

AOM is often confused with otitis media with effusion, or fluid behind the ear, a condition that generally does not involve bacteria and does not benefit from antimicrobial treatment.

From Science Daily • Mar. 4, 2024

Some at Asbury said they preferred the term “outpouring,” as in an almost tangible effusion of the Holy Spirit.

From New York Times • Feb. 23, 2023

The observatory on Thursday raised Kilauea’s alert level, but on Friday morning lowered it from warning to watch “because the initial high effusion rates are declining, and no infrastructure is threatened.”

From Seattle Times • Jan. 6, 2023

The doctor asked me to cough, took my temperature and blood pressure, applied his stethoscope, and announced that I had pleurisy with effusion, pre-tubercular.

From "The Hiding Place" by Corrie ten Boom