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effluvium

American  
[ih-floo-vee-uhm] / ɪˈflu vi əm /

noun

plural

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


effluvium British  
/ ɛˈfluːvɪəm /

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

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.

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Vocabulary lists containing effluvium

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Evidently, telogen effluvium happens when the body undergoes emotional, physical or hormonal shock and pushes more hairs than usual into the resting phase.

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

If your hair-pull test is positive and your scalp does not show signs of redness or scarring, which are indicators of other types of hair loss, you most likely have telogen effluvium.

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