What does "scab" mean?

Scab: The itch in man; also, the scurvy. [Colloq. or Obs.]

Additional senses

  1. 2.The mange, esp. when it appears on sheep. Chaucer.
  2. 3.A disease of potatoes producing pits in their surface, caused by a minute fungus (Tiburcinia Scabies).
  3. 4.(Founding) A slight iregular protuberance which defaces the surface of a casting, caused by the breaking away of a part of the mold.
  4. 5.A mean, dirty, paltry fellow. [Low] Shak.
  5. 6.A nickname for a workman who engages for lower wages than are fixed by the trades unions; also, for one who takes the place of a workman on a strike. [Cant]
  6. 7.To become covered with a scab; as, the wound scabbed over.

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