The Collaborative International Dictionary of English v.0.48:

Scurf \Scurf\, n. [AS. scurf, sceorf, or from Scand.; cf. Sw.
   skorf, Dan. skurv, Icel. skurfur, D. schurft, G. schorf; all
   akin to AS. scurf, and to AS. sceorfan to scrape, to gnaw, G.
   sch["u]rfen to scrape, and probably also to E. scrape. Cf.
   Scurvy.]
   1. Thin dry scales or scabs upon the body; especially, thin
      scales exfoliated from the cuticle, particularly of the
      scalp; dandruff.
      [1913 Webster]

   2. Hence, the foul remains of anything adherent.
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            The scurf is worn away of each committed crime.
                                                  --Dryden.
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   3. Anything like flakes or scales adhering to a surface.
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            There stood a hill not far, whose grisly top
            Belched fire and rolling smoke; the rest entire
            Shone with a glossy scurf.            --Milton.
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   4. (Bot.) Minute membranous scales on the surface of some
      leaves, as in the goosefoot. --Gray.
      [1913 Webster]

WordNet (r) 3.0 (2006):

scurf
    n 1: (botany) a covering that resembles scales or bran that
         covers some plant parts
    2: a thin flake of dead epidermis shed from the surface of the
       skin [syn: scale, scurf, exfoliation]

Moby Thesaurus II by Grady Ward, 1.0:

53 Moby Thesaurus words for "scurf":
   bilge, bilgewater, canaille, carrion, chip, corruption, dandruff,
   decay, dishwater, ditchwater, excrement, filth, flake, floccule,
   flocculus, flock, foul matter, furfur, gangrene, garbage,
   hoi polloi, masses, mess, mob, muck, mucus, obscenity, offal,
   offscourings, ordure, other half, paring, proletariat, pus,
   putrid matter, refuse, riffraff, rot, scale, scum, scuz, sewage,
   sewerage, shaving, slime, slop, slops, slough, smut, snot, sordes,
   swill, trash