Longman Dictionary of Contemporary English homepage

Date: 1600-1700
Origin: Probably from slush

sludge

noun
     
Related topics: Nature, Industry
sludge [uncountable]
1DN soft thick mud, especially at the bottom of a liquid
2TI the solid substance that is left when industrial waste or sewage (=the liquid waste from toilets) has been cleaned
3TTC thick dirty oil in an engine
sludgy adjective

Dictionary pictures of the day
Do you know what each of these is called?
What is the word for picture 1? What is the word for picture 2? What is the word for picture 3? What is the word for picture 4?
Click on any of the pictures above to find out what it is called.

Explore our topic dictionary