a crust of hardened blood and serum over a wound
mange or scabies of domestic animals, esp mange of sheep caused by a parasitic mite
any of various plant diseases characterized by crusted spots, or one of these spots itself
informal
a contemptible person
a strikebreaker or a person brought in to replace striking employees
scabby adj
[Middle English from Old Norse skab; (sense 4) prob by association with early Dutch schabbe slut]