scumnoun/skʌm/

• 1

  A layer of impurities that accumulates at the surface of a liquid (especially molten metal or water).

  • During smelting, scum rises to the surface and is then removed by the smelter.
• 2

  A greenish water vegetation (such as algae), usually found floating on the surface of ponds

  • These organisms form scum in large quantities.
• 3

  The topmost liquid layer of a cesspool or septic tank.

• 4

  slangSemen.

  • Horse, who was always talking about facts, said, “Man, that can't be scum, ’cause scum is white.”
• 5

  derogatoryslangA reprehensible person or persons.

  • People who sell used-up pens are scum, just total low-lives.

scumverb/skʌm/

• 1

  To remove the layer of scum from (a liquid etc.).

• 2

  To remove (something) as scum.

  • Some scumd the drosse, that from the metall came; / Some stird the molten owre with ladles great[…].
• 3

  To become covered with scum.

  • Take the smallest Cucumbers you can get, and as free from Spots as possible, put them into a strong Salt and Water for nine or ten Days, or 'till they are quite Yellow, and stir them twice a Day at least, or they will scum over, and grow soft
• 4

  obsoleteTo scour (the land, sea, etc.).

  • SOo by Merlyns aduys ther were sente fore rydars to skumme the Countreye / & they mette with the fore rydars of the north / and made hem to telle whiche wey the hooste cam / and thenne they told it to Arthur / and by kyng Ban and Bors counceill they lete brenne and destroye alle the contrey afore them there they shold ryde
  • Wandering up and down without certain seat, they lived by scumming those seas and shores as pirates.
• 5

  obsoleteTo gather together, as scum.

  • A great majority of the members are scummed together from the Jacobinical dregs of former periods of the revolution.
• 6

  informalvideo-gamesTo startscum or savescum.