ef·flu·ent
ˈe-ˌflü-ənt 
e-ˈflü-,
ə-
: 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
Julie Gallant, San Diego Union-Tribune, 21 Jan. 2025
Thresholds limiting the concentration of effluent streams could further limit the ability of companies like Ebb to scale.
—IEEE Spectrum, 26 Dec. 2024
U T Editorial Board, San Diego Union-Tribune, 24 Jan. 2025
In some areas, industries may suffer, too, for lack of water to cool machinery, generate hydropower, and flush effluents downstream.
—Scott Moore, Foreign Affairs, 29 May 2016
See all Example Sentences for effluent 
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Adjective
The 14-inch line limited the plant’s ability to pump wastewater to the storage ponds at Rangeland Road, which increased the risk of a potential effluent spill, according to a staff report.
—Julie Gallant, San Diego Union-Tribune, 21 Jan. 2025
Thresholds limiting the concentration of effluent streams could further limit the ability of companies like Ebb to scale.
—IEEE Spectrum, 26 Dec. 2024
Noun
Yet to hear it from a veteran of San Diego’s congressional delegation, the biggest news of late is the final approval of an additional $250 million in federal funding to repair and upgrade the South Bay International Wastewater Treatment Plant in San Ysidro, which cleans up Tijuana’s effluent.
—U T Editorial Board, San Diego Union-Tribune, 24 Jan. 2025
In some areas, industries may suffer, too, for lack of water to cool machinery, generate hydropower, and flush effluents downstream.
—Scott Moore, Foreign Affairs, 29 May 2016
See all Example Sentences for effluent
Cite this Entry
“Effluent.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/effluent. Accessed 8 Feb. 2025.
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