What is "scummed"

Scum \Scum\, v. t. [imp. & p. p. Scummed; p. pr. & vb. n. Scumming.]

1. To take the scum from; to clear off the impure matter from the surface of; to skim.

   You that scum the molten lead.
   --Dryden & Lee.

2. To sweep or range over the surface of. [Obs.]

   Wandering up and down without certain seat, they lived by scumming those seas and shores as pirates.
   --Milton.

vb. (en-past of: scum)

1. n. worthless people [syn: trash]

2. a film of impurities or vegetation that can form on the surface of a liquid

3. [also: scumming, scummed]

See scum