mass nounmass noun
1A layer of dirt or froth on the surface of a liquid.
film, layer, covering, froth, foam, suds, dross, dirtView synonyms
- ‘green scum found on stagnant pools’
2 informal, derogatory A worthless or contemptible person or group of people.
despicable people, despicable person, rabble, riff-raff, refuse, garbage, trash, vermin, good-for-nothing, good-for-nothings, undesirable, undesirables, the lowest of the low, the dregs of societyView synonyms
- ‘you drug dealers are the scum of the earth’
- ‘he's a better man than any of you scum’
transitive verbtransitive verb scums, transitive verb scumming, transitive verb scummed[with object]
1Form a layer of dirt or froth on (a liquid)‘litter scummed the surface of the water’
- ‘the lake shore was scummed with dead weed’
- 1.1no object (of a liquid) become covered with a layer of dirt or froth.
- ‘the lagoon scummed over’
Middle English from Middle Low German, Middle Dutch schūm, of Germanic origin.