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.

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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

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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

What’s more, he estimated that about 30 homes were “red tagged,” or currently deemed unsafe to inhabit, after debris flows choked homes with pounds and pounds of sludge.

From Los Angeles Times

Today, much of that material ends up in the sewage sludge produced at wastewater treatment plants.

From Science Daily

Images taken at the time revealed that the waterway, which runs alongside the property, had risen to dangerous levels and was filled with sludge and debris.

From MarketWatch

In the open sewer outside, plastic bags and bottles drift through charcoal-grey sludge, its stench thick in the air.

From BBC

Residents at the time described seeing slurry carrying "trees and big boulders", and buildings left deep in sludge and mud.

From BBC

Related Words

• goo
• grease
• gunk
• muck
• sediment
• silt
• slime