from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A filmy or frothy layer of matter that forms on the surface of a liquid or body of water or on a hard surface.
  • noun The refuse or dross of molten metals.
  • noun Refuse or worthless matter.
  • noun Slang One, such as a person or an element of society, that is regarded as despicable or worthless.
  • intransitive verb To remove the scum from.
  • intransitive verb To become covered with scum.

from The Century Dictionary.

  • noun Foam; froth: as, the scum of the sea.
  • noun The impurities or extraneous substances which rise to the surface of liquids, as in boiling or fermentation, or which form by other means; also, the scoria of molten metals; hence, by extension, any film or surface of foul floating matter: as, the scum of a stagnant pond.
  • noun Refuse; dross; offscourings.
  • To remove the scum from; clear off the froth, dross, or impurities that have risen to or formed on the surface of; skim.
  • To sweep over; move swiftly upon; skim.
  • To arise or be formed on the surface as foam or scum; be thrown up as scum.
  • To be or become covered with scum: generally with over.
  • To skim lightly: with over.

from the GNU version of the Collaborative International Dictionary of English.

  • intransitive verb To form a scum; to become covered with scum. Also used figuratively.
  • transitive verb To take the scum from; to clear off the impure matter from the surface of; to skim.
  • transitive verb obsolete To sweep or range over the surface of.
  • noun The extraneous matter or impurities which rise to the surface of liquids in boiling or fermentation, or which form on the surface by other means; also, the scoria of metals in a molten state; dross.
  • noun refuse; recrement; anything vile or worthless.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun uncountable A layer of impurities that accumulates at the surface of a liquid (especially molten metal or water).
  • noun uncountable A greenish water vegetation (such as algae), usually found floating on the surface of ponds
  • noun The topmost liquid layer of a cesspool or septic tank.
  • noun countable (derogatory, slang) A reprehensible person or persons.
  • verb To remove the layer of scum from (a liquid etc.).
  • verb To remove (something) as scum.
  • verb obsolete To scour (the land, sea etc.).

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun worthless people
  • verb remove the scum from
  • noun a film of impurities or vegetation that can form on the surface of a liquid


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English, from Middle Dutch schūm; see (s)keu- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Middle English scum, scom, from Old English *scūm ("foam") or Middle Dutch schūme ("foam"), both from Proto-Germanic *skūmaz (“froth, foam”), from Proto-Indo-European *skeu- (“to cover, conceal”). Cognate with Dutch schuim ("foam"), German Schaum ("foam"), Danish and Swedish skum ("foam"). Compare also French écume ("scum"), Italian schiuma ("foam") from the same Germanic source. Related to skim.


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  • "During this period (the late 1960s), Valerie Solanas wrote and self-published the work for which she is best known — a call for destruction of men and men-loving women, as well as the liberation of women, called the SCUM Manifesto. SCUM is generally held to be an acronym of "Society for Cutting Up Men," although this acronym does not appear in the manifesto itself. SCUM gained Solanas a following among some feminists."

    December 9, 2007

  • Citation on pus.

    June 22, 2008