\ ˈsləj How to pronounce sludge (audio) \

Definition of sludge

1 : mud, mire especially : a muddy deposit (as on a riverbed) : ooze
2 : a muddy or slushy mass, deposit, or sediment: such as
a : precipitated solid matter produced by water and sewage treatment processes
b : muddy sediment in a steam boiler
c : a precipitate or settling (such as a mixture of impurities and acid) from a mineral oil

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Other Words from sludge

sludgy \ ˈslə-​jē How to pronounce sludgy (audio) \ adjective

Synonyms for sludge


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Examples of sludge in a Sentence

after a day of heavy rain, the fairgrounds had turned into pure sludge I can't bring myself to read that sludge.
Recent Examples on the Web The plant could also burn sludge from Anchorage Water & Wastewater Utility, eliminating the need for a new $100 million incinerator for the utility, Spafford said. USA TODAY, "Rosa Parks statue, newborn polar bear cub, quake rocks Oregon: News from around our 50 states," 2 Dec. 2019 Six pipe breaks in December left rivers tainted, streets full of sludge, and even some homes barely habitable from the smell alone. Tim Pearce, Washington Examiner, "Florida mayor pleads for help after city swamped in 211M gallons of sewage," 18 Feb. 2020 Five students survived the disaster thanks to the quick thinking of dinner lady Nansi Williams, who sacrificed herself by shielding them from the sludge with her own body. Meilan Solly, Smithsonian, "The True Story of the Aberfan Disaster," 15 Nov. 2019 Spafford said in addition to fixing the landfill problem, an incineration plant could burn sludge from Anchorage Water & Wastewater Utility. Aubrey Wieber, Anchorage Daily News, "Anchorage will explore building a garbage incineration plant to tackle landfill capacity concerns," 28 Nov. 2019 Then there are the recent oil pipeline spills in the Gulf of Mexico and elsewhere, as well as rollbacks that have permitted the reintroduction of coal sludge into streams and rivers. Chuck Yarborough, cleveland, "True-life legal thriller ‘Dark Waters’ serves as a warning similar shoals may lie ahead," 2 Dec. 2019 The site also has about 21 tanker rail cars containing phosphorus sludge the company buried rather than clean up, court documents say. Washington Post, "Court: Company must pay for toxic waste on Idaho tribal land," 19 Nov. 2019 Salles said more than 100 tons of oil sludge has already been collected. Alessandra Castelli And Tara John, CNN, "Mysterious Brazilian oil spill could be 'criminal,' Bolsonaro says," 9 Oct. 2019 Cosmopolitanism — the idea of moral community among human beings, regardless of social and political affiliation — is alive and well, in spite of whatever iniquitous sludge might ooze out from 1600 Pennsylvania Ave. Los Angeles Times, "The 11 best art exhibitions to see in L.A. this fall," 12 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sludge.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of sludge

15th century, in the meaning defined at sense 1

History and Etymology for sludge

Middle English slugge, perhaps alteration of slicche mud, slush; akin to Old High German slīh mire

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Time Traveler for sludge

Time Traveler

The first known use of sludge was in the 15th century

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Statistics for sludge

Last Updated

31 Mar 2020

Cite this Entry

“Sludge.” Dictionary, Merriam-Webster, Accessed 3 Apr. 2020.

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How to pronounce sludge (audio)

English Language Learners Definition of sludge

: thick, soft, wet mud
: a soft, thick material that is produced in various industrial processes (such as in the treatment of sewage)
: a thick material that can form in the oil in an engine and cause engine problems


\ ˈsləj How to pronounce sludge (audio) \

Kids Definition of sludge

: a soft muddy mass resulting from sewage treatment


\ ˈsləj How to pronounce sludge (audio) \

Medical Definition of sludge

 (Entry 1 of 2)

: a semisolid precipitated mass or deposit biliary sludge especially : sludged blood
sludged; sludging

Medical Definition of sludge (Entry 2 of 2)

: to form sludge positions that cause blood to sludge— L. K. Altman

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More from Merriam-Webster on sludge

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Rhyming Dictionary: Words that rhyme with sludge

Spanish Central: Translation of sludge

Nglish: Translation of sludge for Spanish Speakers

Britannica English: Translation of sludge for Arabic Speakers

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