Scum

Scum or S.C.U.M. may refer to:

== Scum == Soap scum, an informal term for the white solid that results from the addition of soap to hard water Impurity that accumulates at the surface of a liquid (especially water or molten metal) Dross, solid impurities floating on a molten metal Algae or similar vegetation found floating on the surfaces of ponds The topmost liquid layer in a septic tank, mainly consisting of fats