What does "scum" mean?

Scum: refuse; recrement; anything vile or worthless. The great and innocent are insulted by the scum and refuse of the people. Addison.

Additional senses

  1. 2.To take the scum from; to clear off the impure matter from the surface of; to skim. You that scum the molten lead. Dryden & Lee.
  2. 3.To sweep or range over the surface of. [Obs.] Wandering up and down without certain seat, they lived by scumming those seas and shores as pirates. Milton.
  3. 4.To form a scum; to become covered with scum. Also used figuratively. Life, and the interest of life, have stagnated and scummed over. A. K. H. Boyd.

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