sludge

See also: SLUDGE

English

English Wikipedia has an article on:

sludge

Wikipedia

Etymology

Possibly related to slush.

Pronunciation

• IPA^(key): /slʌd͡ʒ/

• Audio (Southern England):

  (file)

• Audio (US):

  (file)

• Rhymes: -ʌd͡ʒ

Noun

sludge (countable and uncountable, plural sludges)

1. Solids separated from suspension in a liquid.
   • 2013 June 29, “High and wet”, in The Economist, volume 407, number 8842, page 28:

     Floods in northern India, mostly in the small state of Uttarakhand, have wrought disaster on an enormous scale. […] Rock-filled torrents smashed vehicles and homes, burying victims under rubble and sludge.

2. A residual semi-solid material left from industrial, water treatment, or wastewater treatment processes.
3. A sediment of accumulated minerals in a steam boiler.
4. A mass of small pieces of ice on the surface of a water body.
5. (uncountable, music) Ellipsis of sludge metal.
6. (behavioral science) Institutional policies that introduce tedium and inefficiency in processes.
   • [2025 June 29, Chris Colin, “That Dropped Call With Customer Service? It Was on Purpose.”, in The Atlantic‎, retrieved 29 June 2025, Ideas:

     In the 2008 best seller Nudge, the legal scholar Cass R. Sunstein and the economist Richard H. Thaler marshaled behavioral-science research to show how small tweaks could help us make better choices. An updated version of the book includes a section on what they called “sludge”—tortuous administrative demands, endless wait times, and excessive procedural fuss that impede us in our lives.]

Synonyms

• (separated solids): mire, mud, ooze, slush

Derived terms

• activated sludge
• biliary sludge
• oil sludge
• primordial sludge
• sludge acid
• sludgecore
• sludge hole
• sludge metal
• sludge out

Translations

generic term for separated solids

Chinese: Mandarin: 污泥 (zh) (wūní) Esperanto: ŝlimo Finnish: liete (fi), lieju (fi), muta (fi) French: lie (fr) f German: Schlamm (de) m, Matsch (de) m Irish: dríodar m Japanese: 泥 (ja) (どろ, doro), 泥土 (ja) (でいど, deido) Korean: 진흙 (ko) (jinheuk), 진창 (jinchang) Maori: kene Plautdietsch: Moarauss m Portuguese: sedimento (pt) m Russian: шлам (ru) m (šlam), ил (ru) m (il) Spanish: lodo (es) m, sedimento (es) m, puaj (es) m, fango (es) m Ukrainian: мул m (mul)

residual material from a process

Arabic: حَمَأ (ḥamaʔ), حَمأَة f Bulgarian: шлам m (šlam) Finnish: liete (fi) German: Abwasserschlamm m Irish: dríodar m Maori: kene Polish: szlam (pl) m, muł (pl) m Russian: оса́док (ru) m (osádok) Spanish: fango (es) m Turkish: atık (tr), çamur (tr), tortu (tr)

sediment of minerals in a steam boiler

Arabic: رُسَابَة f (rusāba) Bulgarian: накип m (nakip) Finnish: kattilakivi (fi) Russian: шлам (ru) m (šlam) Spanish: lodo (es) m

small pieces of ice

Bulgarian: плаващ лед m (plavašt led) Finnish: suppo (fi), hyhmä (fi), sohjo (fi) Spanish: costra (es) f

Verb

sludge (third-person singular simple present sludges, present participle sludging, simple past and past participle sludged)

1. (intransitive, informal) To slump or slouch.
2. (intransitive) To slop or drip slowly.