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Synonyms

scum

American  
[skuhm] / skʌm /

noun

  1. a film or layer of foul or extraneous matter that forms on the surface of a liquid.

  2. refuse or offscourings.

  3. a low, worthless, or evil person.

  4. such persons collectively; riffraff; dregs.

  5. scoria.


verb (used with object)

scummed, scumming
  1. to remove the scum from.

  2. to remove as scum.

verb (used without object)

scummed, scumming
  1. to form scum; become covered with scum.

scum British  
/ skʌm /

noun

  1. a layer of impure matter that forms on the surface of a liquid, often as the result of boiling or fermentation

  2. the greenish film of algae and similar vegetation surface of a stagnant pond

  3. Also called: dross.   scruff.  the skin of oxides or impurities on the surface of a molten metal

  4. waste matter

  5. a worthless person or group of people

"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

verb

  1. (tr) to remove scum from

  2. rare (intr) to form a layer of or become covered with scum

"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

  • scumless adjective
  • scumlike adjective
  • scummer noun
  • unscummed adjective

Etymology

Origin of scum

1200–50; Middle English scume < Middle Dutch schūme ( Dutch schuim ) foam; cognate with German Schaum foam

Vocabulary lists containing scum

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.

The first is a “caution” advisory, which indicates visitors can swim but should stay away from algae and scum in the water.

From Los Angeles Times • Aug. 22, 2024

For most people, the word “algae” evokes puddles of puke-brown scum.

From Science Magazine • May 21, 2024

On Earth, ocean scum is a key part of sea spray that contributes to the smell of the ocean.

From Science Daily • Mar. 22, 2024

Adding a small squeeze of lemon juice can also remove the "scum" that sometimes appears on the surface of the drink, she adds.

From BBC • Jan. 24, 2024

I want to say l am scum because I feel like scum.

From "Ask the Passengers" by A.S. King