Pronunciation: (skum), [key]
—n., v., scummed, scum•ming.
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 (def. 1).
1. to remove the scum from.
2. to remove as scum.
to form scum; become covered with scum.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.