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

3

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

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. —Houston Mitchell, Los Angeles Times, 4 Dec. 2024

Pleural effusion: The tissue that lines the chest cavity and surrounds the lungs can become diseased or inflamed, causing the lungs to fill with fluid. —Mark Gurarie, Verywell Health, 30 Oct. 2024

Schröder had been dealing with right Achilles soreness, Smith with right hip synovitis and Finney-Smith with a left knee effusion. —C.j. Holmes, New York Daily News, 12 Apr. 2024

His great achievement, and Moses’s and Neugebauer’s, lies in the fact that such an effusion — hardly the only one in The Ally — feels not only truthful but real, earned and human, an expression not of writerly grandiosity but of character need. —Sara Holdren, Vulture, 28 Feb. 2024

Word History

Etymology

Middle English effusioun "emission, shedding," borrowed from Anglo-French effusiun, borrowed from Latin effūsiōn-, effūsiō, from effud-, variant stem of effundere "to pour out, discharge, expend" + -tiōn-, -tiō, suffix of action nouns — more at effuse entry 1

First Known Use

15th century, in the meaning defined at sense 1

Kids 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