effluent

1 of 2

adjective

ef·​flu·​ent ˈe-ˌflü-ənt How to pronounce effluent (audio)
e-ˈflü-,
ə-
: flowing out : emanating, outgoing
an effluent river

effluent

2 of 2

noun

: something that flows out: such as
a
: an outflowing branch of a main stream or lake
b
: waste material (such as smoke, liquid industrial refuse, or sewage) discharged into the environment especially when serving as a pollutant

Did you know?

Effluent comes from the Latin verb effluere, "to flow out". In an older meaning, an effluent was a stream flowing out of a river or lake. But nowadays effluent almost always means wastes that pour into our water and air. Liquid factory waste, smoke, and raw sewage can all be called effluents. An effluent filter keeps treated waste flowing out of a septic tank from clogging up its drainage pipes.

Examples of effluent in a Sentence

Noun The factory has been accused of discharging effluent into the river.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
Jun and Arthur finish their effluent business by the time J finishes his own. Literary Hub, 15 Aug. 2025 However, Water and Wastewater Authority of Wilson County Director Chris Leauber says flowing water from the facility is stormwater and that effluent sample readings the wastewater authority has done are a lower number than what the notice says. Andy Humbles, The Tennessean, 13 Aug. 2025
Noun
Beneficial bacteria in the tank break down organic waste, while liquid effluent flows out into the drain field for further filtration. Timothy Dale, Better Homes & Gardens, 14 Aug. 2025 Pan said in a statement that menstrual effluent (blood and tissue) shed from the uterus each month is often overlooked as medical waste—and even stigmatized by some—but could help with earlier and more accessible endometriosis detection. Health Reporter, MSNBC Newsweek, 24 July 2025 See All Example Sentences for effluent

Word History

Etymology

Adjective

Latin effluent-, effluens, present participle of effluere to flow out, from ex- + fluere to flow — more at fluid

First Known Use

Adjective

1726, in the meaning defined above

Noun

1859, in the meaning defined above

Time Traveler
The first known use of effluent was in 1726

Browse Nearby Words

Cite this Entry

“Effluent.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/effluent. Accessed 8 Sep. 2025.

Kids Definition

effluent

noun
ef·​flu·​ent
ˈef-ˌlü-ənt;
e-ˈflü-,
ə-
: liquid (as sewage or industrial by-products) discharged as waste
effluent adjective
Last Updated: - Updated example sentences
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