1. a layer of froth or foam that forms on the surface of a liquid
2. a worthless or contemptible person
Usage: informal; derogatory

1. to remove scum from the surface of a liquid
2. to become covered with scum

Examples

• Green scum covered the surface of the stagnant pond.
• She carefully skimmed the scum off the boiling soup.
• The chef scummed the broth to make it clear.
• Algae scum formed on the aquarium glass.
• The old well water had developed a thick scum.
• He used a ladle to scum the fat from the stew.