sludge

noun

ˈsləj 

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

3

: slush sense 5

sludgy

ˈslə-jē 

adjective

Synonyms

• guck
• gook
• mire
• muck
• mud
• ooze
• slime
• slop
• slush

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 return of sludge haulers have made a difference for Andrea Chiarella’s daily walks. —Douglas Hanks, Miami Herald, 7 Feb. 2025

Soon, snowmen will soon melt into brown piles of sludge and green grass will appear again. —Karissa Waddick, USA TODAY, 24 Jan. 2025

Following their stunning Super Bowl XVI victory in suburban Detroit over the Cincinnati Bengals, the Niners endured two seasons of sludge and vexation that concluded with a controversial playoff loss. —Mark Purdy, The Mercury News, 24 Jan. 2025

There's a Lawrenceville location, too. ☕️ Pro tip: Sip slowly to avoid a mouthful of finely ground sludge at the bottom of the cup. —Ryan Deto, Axios, 24 Feb. 2025

Word History

Etymology

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

First Known Use

15th century, in the meaning defined at sense 1

Rhymes for sludge

• budge
• drudge
• frage
• fudge
• grudge
• judge
• mudge
• nudge
• rudge
• smudge
• trudge
• adjudge

Kids Definition

sludge

noun

ˈsləj 

1

: mud, mire

2

: a muddy or slushy mass

especially : solid matter produced by water and sewage treatment processes

sludgy

ˈsləj-ē 

adjective

Medical Definition

sludge

1 of 2 noun

ˈsləj 

: a semisolid precipitated mass or deposit

biliary sludge

especially : sludged blood

sludge

2 of 2 intransitive verb

sludged; sludging

: to form sludge

positions that cause blood to sludge

—L. K. Altman