effluvium

noun

ef·​flu·​vi·​um e-ˈflü-vē-əm How to pronounce effluvium (audio)
variants or less commonly effluvia
plural effluvia also effluviums
1
: an invisible emanation
especially : an offensive exhalation or smell
2
: a by-product especially in the form of waste

Examples of effluvium in a Sentence

the effluvia from local sewage treatment plants polluting the river

Word History

Etymology

Latin effluvium act of flowing out, from effluere

First Known Use

1651, in the meaning defined at sense 1

Time Traveler
The first known use of effluvium was in 1651

Browse Nearby Words

Cite this Entry

“Effluvium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/effluvium. Accessed 24 Jun. 2025.

Medical Definition

effluvium

noun
ef·​flu·​vi·​um e-ˈflü-vē-əm How to pronounce effluvium (audio)
plural effluvia -vē-ə How to pronounce effluvium (audio) or effluviums
: an invisible emanation
especially : an offensive exhalation or smell
the form effluvia often used with a singular verb

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