\ 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

Other Words from sludge

sludgy \ ˈslə-​jē How to pronounce sludge (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 Cities have also begun to use the sludge as a source of energy. Eleanor Cummins, The New Republic, 3 Feb. 2022 Black Flag’s piercing hardcore and Sabbathy sludge shared little with the Minutemen’s springy, spiky punk-jazz fusion, the Meat Puppets’ Dead-like excursions or Hüsker Dü’s blend of pop savvy and stun guitar. Mark Athitakis, Los Angeles Times, 12 Apr. 2022 Not enough time to fall in love with gluten, grow a slight paunch, tame his golf swing, or find a wooden bench outside a tackle shop where everyone gossips and drinks sludge coffee. Jason Gay, WSJ, 14 Mar. 2022 Robert Chandler absolutely loves his property next to the sludge farm. Dennis Pillion |, al, 3 Mar. 2022 The night before the retreat, however, Ashworth found herself in a Los Angeles dive bar where sludge metal band Barishi was performing. Matt Sigur, SPIN, 23 Feb. 2022 However, residents living near sites where the sludge is applied often complain of oppressive odors. Dennis Pillion |, al, 19 Apr. 2022 At Patapsco, one of the problems has been tied to difficulties processing the sludge removed from the plant. Christine Condon, Baltimore Sun, 13 Apr. 2022 Gasoline has shorter chains than diesel, which, in turn, has shorter chains than bunker fuel, the gunky sludge used to power cargo ships. Robinson Meyer, The Atlantic, 16 Mar. 2022 See More

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.

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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Dictionary Entries Near sludge



sludge acid

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Statistics for sludge

Last Updated

17 May 2022

Cite this Entry

“Sludge.” Dictionary, Merriam-Webster, Accessed 17 May. 2022.

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More Definitions for sludge


\ 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


intransitive verb
sludged; sludging

Medical Definition of sludge (Entry 2 of 2)

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

More from Merriam-Webster on sludge

Nglish: Translation of sludge for Spanish Speakers

Britannica English: Translation of sludge for Arabic Speakers


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