noun
- a thin layer of impurities which forms on the top of liquids or bodies of water, often as the result of boiling or fermentation
- the dross or refuse on top of molten metals
- worthless parts or things; refuse
- Informal a low, despicable person, or such people collectively; lowlife
Origin:
ME < MDu schum, akin to Ger schaum, foam, scum, prob. < IE base *(s)keu-, to cover > sky
transitive verb scummed, scumming
to remove scum from; skim
intransitive verb
to form scum; become covered with scum