effusion
noun
ef·fu·sion
i-ˈfyü-zhən 
e-
1
: an act of effusing
2
: unrestrained expression of words or feelings
greeted her with great effusion—
Olive H. Prouty
Olive H. Prouty3
a(1)
: the escape of a fluid from anatomical vessels by rupture or exudation
(2)
: the flow of a gas through an aperture whose diameter is small as compared with the distance between the molecules of the gas
b
: the fluid that escapes
Examples of effusion in a Sentence
Her poetic effusions became tiresome.
Recent Examples on the Web
And as Brown’s book races toward its elaborate climax, his (and Langdon’s) breathless effusions about the neuro-technological progress that awaits us sound jarringly out of sync with the anxious, doomy present.
—Book Marks
september 11, Literary Hub, 11 Sep. 2025
Managing underlying conditions such as arthritis or infection can also be effective in treating knee effusion.
—Lana Barhum, Verywell Health, 16 Aug. 2025
After her kidney was removed without her consent, Rappaport was diagnosed with respiratory failure, left pleural effusion, diastolic heart failure and Stage 5 kidney disease, according to the lawsuit.
—Jennifer Rodriguez, Kansas City Star, 20 May 2025
Pleural effusion: Pleural effusion occurs as a complication of bacterial pneumonia when fluid builds up between the lungs and chest wall.
—Lindsay Curtis, Health, 13 Apr. 2025
See All Example Sentences for effusion
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Book Marks
september 11, Literary Hub, 11 Sep. 2025
Managing underlying conditions such as arthritis or infection can also be effective in treating knee effusion.
—Lana Barhum, Verywell Health, 16 Aug. 2025
After her kidney was removed without her consent, Rappaport was diagnosed with respiratory failure, left pleural effusion, diastolic heart failure and Stage 5 kidney disease, according to the lawsuit.
—Jennifer Rodriguez, Kansas City Star, 20 May 2025
Pleural effusion: Pleural effusion occurs as a complication of bacterial pneumonia when fluid builds up between the lungs and chest wall.
—Lindsay Curtis, Health, 13 Apr. 2025
See All Example Sentences for effusion
Cite this Entry
“Effusion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/effusion. Accessed 3 Nov. 2025.
Copy CitationKids Definition
effusion
noun
ef·fu·sion
i-ˈfyü-zhən
e-
1
: free expression of words or feelings
2
a
: escape of a fluid from containing vessels
b
: the fluid that escapes
Medical Definition
effusion
noun
ef·fu·sion
i-ˈfyü-zhən, e-
1
a
: the escape of a fluid from anatomical vessels by rupture or exudation
b
: the flow of a gas through an aperture whose diameter is small as compared with the distance between the molecules of the gas
2
: the fluid that escapes by extravasation see pleural effusion
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