[U, pl.] (informal) an insulting word for people that you strongly disapprove of （骂人的话）渣滓，败类
Don’t waste your sympathy on scum like that.
对这样的渣滓你没必要同情。
Drug dealers are the scum of the earth (= the worst people there are).
毒品贩子是社会渣滓。
scummy water
有浮垢的水
scummy people dropping litter
不讲公德、乱丢杂物的
scum
/skʌm/
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An insulting word for people that you strongly disapprove of （骂人的话）渣滓，败类