Dict: strongs - scum

Strongs:

H2457 @ חלאה chel'âh khel-aw' From H2456; properly disease; hence rust: - scum.

H2560 @ חמר châmar khaw-mar' A primitive root; properly to boil up; hence to ferment (with scum); to glow (with redness); as denominative (from H2564) to smear with pitch: - {daub} {foul} be {red} trouble.

G4067 @ περίψωμα peripsōma per-ip'-so-mah From a compound of G4012 and psao (to rub); something brushed all around that is off scrapings (figuratively scum): - offscouring.