effluvium

American  

[ih-floo-vee-uhm] / ɪˈflu vi əm /

noun

effluvia, plural effluviums plural

1. a slight or invisible exhalation or vapor, especially one that is disagreeable or noxious.

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effluvium British  

/ ɛˈfluːvɪəm /

noun

1. an unpleasant smell or exhalation, as of gaseous waste or decaying matter

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Other Word Forms

• effluvial
  adjective

Etymology

Origin of effluvium

1640–50; < Latin, equivalent to ef- ef- + fluv-, base of fluere to flow ( see effluent) + -ium -ium

Explanation

Effluvium is a smelly gas, vapor, or an exhalation. You wouldn't want to breathe in the effluvium from a cargo ship or you might become ill. Stick to sailing. Not a particularly common word these days, effluvium dates back to the 1600's, meaning "a flowing out of air." Since the effluvium seeping out of the tire factory's chimney was invisible, park officials took months to realize fumes were killing hundreds of birds. The Romans were the first to invent a sewage system, thereby diverting effluvium into the drains and out of the city. Thank you, Romans.

Example Sentences

It can last three to six months but the silver lining is that telogen effluvium can be reversed.

From Los Angeles Times • Dec. 9, 2025

Unlike genetic or hormone-driven loss, I had a textbook case of telogen effluvium, or stress shedding.

From Los Angeles Times • Dec. 9, 2025

“Telogen effluvium short-circuits the cycle for many hairs,” Garza said.

From Seattle Times • Oct. 10, 2022

Once such undisguised hatred is hurled, its effluvium clings, no matter how much is done to wash it away.

From Washington Times • Jun. 24, 2020

Yes, shadowy: a myth, a phantom: something which they engendered and created whole themselves; some effluvium of Sutpen blood and character, as though as a man he did not exist at all.

From "Absalom, Absalom!" by William Faulkner