(uncountable) A layer of impurities that accumulates at the surface of a liquid (especially molten metal or water).

To remove the layer of scum from (a liquid etc.). / To remove (something) as scum. / To become covered with scum. / (obsolete) To scour (the land, sea etc.). / (obsolete) To gather together, as scum.

(printing) The accumulation of sticky ink on a plate. / (chiefly in the plural) That which is scummed off; skimmings; scum.

(video games, derogatory) The strategy of collecting easy rewards in unchallenging areas, e.g. when a high-level character visits levels suitable for low-level characters in roguelike games.

plural of scum

plural of scumming

simple past tense and past participle of scum

(chiefly Liverpudlian) The Sun newspaper.

dominated or plagued by scum.

(informal, derogatory) An undesirable individual; the worst type of person or people.