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Synonyms

sludge

American  
[sluhj] / slʌdʒ /

noun

  1. mud, mire, or ooze; slush.

  2. a deposit of ooze at the bottom of a body of water.

  3. any of various more or less mudlike deposits or mixtures.

  4. the sediment in a steam boiler or water tank.

  5. broken ice, as on the sea.

  6. a mixture of some finely powdered substance and water.

  7. sediment deposited during the treatment of sewage.

  8. Also called activated sludge.  Bacteriology. sewage sediment that contains a heavy growth of microorganisms, resulting from vigorous aeration.

  9. a fine, mudlike powder produced by a mining drill.

sludge British  
/ slʌdʒ /

noun

  1. soft mud, snow, etc

  2. any deposit or sediment

  3. a surface layer of ice that has a slushy appearance

  4. (in sewage disposal) the solid constituents of sewage that precipitate during treatment and are removed for subsequent purification

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • de-sludge verb (used with object)

Etymology

Origin of sludge

First recorded in 1640–50; variant of dialectal slutch, slitch, Middle English slich “slime, wet mud” (compare its derivative slucched “muddy”); apparently of expressive origin

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But as soon as she got one leg free, the other was sucked into the sticky sludge, her balance already a struggle with that missing front paw.

From Literature

The smog season regularly did a number on our mile-high mountains, wrapping them in a brown cloak of invisibility until wind and rain swept the sludge away.

From Los Angeles Times

He ripped it out, balled it up, then dropped it into the sludge of my ice cream bowl.

From Literature

The arrival of a hurricane means Evie, her little brother, Jack, and the other young people have problems of fresh urgency, including a flood of toxic sludge, that the adults seem unwilling to address.

From The Wall Street Journal

In the city of Uba, a two-hour drive away, residents were covered in mud as they cleared sludge from a river that had burst its banks.

From Barron's

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.