What does "scurf" mean?

Scurf: Hence, the foul remains of anything adherent. The scurf is worn away of each committed crime. Dryden.

Additional senses

  1. 2.Anything like flakes or scales adhering to a surface. There stood a hill not far, whose grisly top Belched fire and rolling smoke; the rest entire Shone with a glossy scurf. Milton.
  2. 3.(Bot.) Minute membranous scales on the surface of some leaves, as in the goosefoot. Gray.

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